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Chapter Text

The first time Izuku Midoriya saw a yokai, he was three years old and convinced it was a cat. The memory clung to him like the humidity of midsummer. His mother had been washing dishes, humming softly, the kitchen a safe and ordinary place. But outside the window, crouched atop the rusted railing, was something with mismatched eyes and fur that shimmered green when the sun hit just right. It watched him with a crooked smile, teeth a little too sharp, tail swishing with mischievous intent.

He waved at it, sticky fingers pressing against the glass, and the creature winked. His mother never noticed. Neither did the old lady across the street, or the cluster of children playing on the cracked pavement, knees dirty and laughter bright. Only him.

At first, everyone thought Izuku’s world was harmless. A bright child with an overactive mind, maybe, inventing stories for lonely afternoons. Adults humored him. They patted his head when he talked about shadowy things in the park, or the strange woman with no face who always wanted to borrow his lunch. kids though, kids remembered. And as years ground by, the stories shifted from endearing to unsettling. The other children grew wary, then cruel. Some called him a liar. Others whispered things he couldn’t hear but always felt, burning in the back of his neck. The world became cold in places adults couldn’t see.

So Izuku learned to keep quiet.

He still saw yokai everywhere. The city crawled with them. Tiny spirits flickering in alleyways, hunched forms lumbering along rooftops at midnight, invisible to everyone but him. There was the one that lived in the school attic, thin and blue and prone to giggles that echoed in the walls. There were the twins in the train station, wrapped in moth-eaten scarves, always whispering about the next train that would never come. They were lonely, mostly. Gentle, always. Izuku liked them. Over time, he stopped trying to make human friends. The yokai were enough. Sometimes, they were all he had.

But friendship with yokai came with a price. Sooner or later, they disappeared. Occasionally, he’d see a flash of white, the edge of a trailing robe, a hint that the master of the Mononokean had come. Izuku’s yokai friends would hush him, trembling a little, begging him not to get involved. “Don’t let the Mononokean master see you,” they’d warn, voices as thin as mist. “Humans aren’t supposed to know. If they find out about you, about what you can do, the big ones in the Underworld will be interested. You don’t want that, do you, Izu-chan?”

He didn’t.

The Mononokean was a story whispered between shadows: A wandering house. Its master was another yokai. A powerful one.

“It’s not bad,” a little kitsune girl once told him. “It’s like going home, that’s all. I’ll be okay.”

Izuku watched his friends leave, one by one, for a place he couldn’t follow. He envied them sometimes. Not the exorcism, but the passage. The simple comfort of belonging somewhere. But the underworld was for yokai, not for him.

On the outside, his life was a litany of small routines. He woke early, packed his lunch, kept his head down at school. Teachers barely looked at him now; he’d learned not to raise his hand, not to speak unless called upon. He was quiet enough that even the bullies sometimes forgot he existed. He counted that as a victory.

After school, while other kids crowded game arcades and convenience stores, Izuku wandered the quiet places. The riverbank, where koi with faces like old men whispered stories in riddles. The overgrown shrine, choked with moss, where a single-eyed tengu perched and picked his teeth with a twig, always eager for gossip. The city was a layered thing, and between the layers, Izuku found a kind of solace.

Sometimes, he helped his yokai friends move on. Not like the Mononokean master, not with doors, but with words, with a hand held tight. Sometimes just a promise to remember them. He never called for the underworld’s gates. He couldn’t. That was the privilege of the Mononokean’s master, not for someone like him. Still, yokai trusted him to help in the small, human ways: finding a lost item, saying goodbye, bearing witness. He took their secrets and stitched them into his heart, heavy and precious.

One evening, as the sun bruised itself against the city’s horizon and streetlights flickered awake, Izuku sat beneath the cracked torii at the shrine. A little spirit, half rabbit half bird, sat beside him, legs swinging through the air. It had been crying, cheeks smudged with silvery tears.

“What’s wrong?” Izuku asked, voice soft so it wouldn’t run.

“I don’t want to go alone,” the yokai whispered, and the fear in its eyes was old as thunder.

He stayed with it, fingers laced together, until the sky was indigo and a doorway opened, just for a moment, at the edge of the shrine grounds. He couldn’t see the master, not really. Trying not to look like he could see him or the door. The rabbit-bird yokai stepped forward, one last glance over its shoulder, and vanished.

After, Izuku watched the shadows grow longer. The world was quiet. He pressed his palm to the dirt, the place where his friend had been. The loneliness was sharp as broken glass, but he didn’t cry.

He stood, brushed himself off, and made his way home, footsteps quiet on the stone. The city pulsed with hidden life, unseen by everyone but him.

Tomorrow, he would wake, and pretend again. He would see things no one else could, and keep those secrets pressed close to his heart. Maybe, someday, he’d find someone else who understood. Someone who could see the layers. But for now, he walked the human world and the yokai world alone, the last bridge between them, and wondered if he would ever belong to either.

The morning sun crawled in slow through the curtains, painting Izuku’s room in a watery gold. He lay awake for several minutes, tracing the cracks in the ceiling with his eyes, not quite ready to leave the softness of his blankets. Down the hall, his mother hummed, the tune trembling and hopeful, a thin thread holding their mornings together. He listened for a minute longer, just her voice, the scrape of her slippers on linoleum, the hush of a kettle beginning to boil.

He finally rolled out of bed, stretching arms that felt too long for his own body, and padded out into the kitchen. His mother stood at the counter, shoulders tense, her back a rigid line. Izuku blinked, squinting - there, just between her shoulder blades, something pale and spidery clung to the fabric of her pajama top. It looked like a jellyfish that had forgotten how to floa. Trailing, boneless tendrils, a pulsing, glimmering body that faded in and out, sometimes almost invisible. When it shifted, she winced, her hand drifting up as if to massage an ache that wouldn’t leave.

Izuku felt a quiet kind of panic flutter in his chest, but he kept his face soft and open, the way he’d practiced. He padded over, making a show of yawning, arms high, and said, “Morning, Mom.”

She managed a smile, though her eyes were pinched. “Good morning, sweetie. Breakfast soon, okay?”

“Can I help?” he asked, stepping close, brushing past her as if just reaching for a mug. The jellyfish yokai shimmered, flickering as it sensed him, its bulbous head quivering. He could hear its soundless humming, feel it prickling at the edge of his thoughts.

His mother shifted her weight, grimacing. “Just… slept wrong again, I guess. My back’s been awful since yesterday.”

He moved behind her, reaching for the dish rack, every movement casual, heart pounding. He murmured, “Hold still a second,” as if he was about to swat a mosquito.

His fingers slipped through the air, brushing the yokai. It recoiled, lashing out with a jelly-soft tendril, but it was barely present here, not built for resistance. He pinched it carefully, gently, thumb and forefinger catching its main body. It fizzed in his grasp, colors rippling up his arm. The feeling was cold, numbing, a static crawling into his wrist. It tried to ooze away, but he tightened his grip, bringing it closer to his chest where it wouldn’t be seen.

The moment he pulled it free, his mother gasped, a tiny sigh, tension bleeding out of her like air from a balloon. She straightened with a relieved, confused noise, rolling her shoulders. “Oh. That’s… better? Huh. I really need a new mattress.”

Izuku dropped his hand to his side, cradling the yokai where she couldn’t see, careful not to let it slip. It writhed, folding in on itself, and for a split second he saw its eyes: Tiny and black, set far apart, confused and mildly annoyed.

“I’ll pour the tea!” he said, sliding in front of her, a distraction, keeping the wriggling yokai tucked against his hip. She shrugged, muttering something about old age, and left the kitchen.

He waited until she’d turned the corner, then hurried to the back door. The morning air was sharp, stinging his bare feet. He knelt at the patch of garden choked by weeds, holding out the little creature. It pulsed once, twice, then slipped from his hand like a drop of water, vanishing beneath the stones with a shimmer.

He let out a breath, shivering. The tips of his fingers were still cold, tingling from the yokai’s presence.

He closed the door quietly and went back inside, careful to smooth the worry from his face. He’d gotten too close to being caught last time. After the therapist, after the tests and the pills he’d never taken. He’d learned how to be invisible in his own house, how to let adults believe what they needed to believe. If he acted strange again, he risked losing the only safe place he had left.

Izuku poured two mugs of tea, hands steady, heart thudding. He set his mother’s mug down gently. She smiled at him, a soft tiredness in her eyes.

“Thank you, Izuku,” she said, squeezing his hand.

He smiled back, careful, small, and took his seat at the table. He let the warmth of the tea chase the chill from his skin and watched the sunlight crawl across the tablecloth, breathing easy as if nothing had ever happened.

But the shadow of the yokai lingered in his mind. Not all of them wanted to speak, or even could. Some just hurt, and drifted on, oblivious to the way their presence twisted things in the human world. Izuku wondered, briefly, if the master of the Mononokean would have been kinder, or harsher, or if the tiny jellyfish spirit would have vanished into the underworld with as little understanding as it had entered.

He knew he’d have to be careful, never draw attention, never be seen by the big ones, especially not the Mononokean’s master.

He pressed his hands together, knuckles white, and finished his tea, the taste bittersweet and lingering.

The school building squatted in the middle of the neighborhood like an old, wounded animal. Its concrete skin was pitted, windows dull, halls echoing with the scrape of too many footsteps and voices. Izuku slipped through the front doors with his shoulders hunched, bag held close, trying to breathe as little and to take up as little space as possible. It didn’t help. It never did.

He slid down the hall, eyes on the floor, letting the laughter and shrill conversations wash over him. It was always the same. They saw him, but they didn’t see him. The giggling started when he was halfway to his classroom, a bright, glassy sound, sharp enough to make his teeth ache. He recognized the voices before he heard the words: Haru and his little court, always looking for something to bite.

“Careful, careful! You might catch Creepyku’s disease!” one girl called, swerving away from him with dramatic arms. “Don’t look at his eyes, he’ll curse you!” another boy laughed, skirting past as if Izuku radiated something infectious.

He kept his head down, pace steady, and ignored them. He was good at ignoring. The words rolled over him, cold but familiar, worn into his skin like old bruises. He liked it this way. He wanted the distance, the circle of empty air around his desk, the silence when he walked through the room. The world shrank to a size that he could manage.

In his classroom, he slid into his seat at the back by the window, bag at his feet, notebook on his desk. He avoided everyone’s eyes, even the teacher’s, and waited for the day to begin. The teacher droned on about fractions and ancient history, chalk dust drifting through the stale air. Izuku’s gaze wandered, drifting over the posters, the back of heads, the yawning stretch of the ceiling. He understood all of it already.

Today, there was a yokai perched in the far corner of the classroom ceiling, a fluffy thing, all feathers and beak and tiny, luminous eyes. It watched the students with its head tilted, a puzzled, hopeful look in its golden face. Izuku looked up at it, not too obviously, letting his gaze linger for a second longer than was normal.

The yokai noticed. It blinked at him, fluffed its wings, and began to preen, a pleased shiver running through its body. Another yokai, small and round like a tangle of thread, sat under the teacher’s desk, rolling back and forth in silent boredom.

Izuku didn’t talk out loud to them, not ever. He’d learned that lesson a long time ago, the first time a teacher caught him whispering to an empty chair, the first time his mother had looked at him with worry. But he could still talk to them, in his way. He opened his notebook and wrote a message on a blank page, small and careful:

Isn´t the teacher as boring as usual?

He left the notebook angled just right, so the yokai on the ceiling could see. It leaned forward, peering down, and let out a tiny, silent hoot, nodding enthusiastically. The thread-yokai beneath the desk spun itself into a tight ball and rolled in a tiny circle, its version of laughter. Izuku smiled to himself, tucking the smile away where no one could see it.

Class dragged on, minutes thick and sticky, the teacher’s voice a dull, endless river. Izuku doodled between the lines of his notes: Tiny birds, spirals, the shapes of yokai he’d seen over the last few days. He flicked his eyes up every so often, just to remind the yokai that he was still there, that he still saw them.

At lunch, he sat in his usual spot at the edge of the courtyard, far from the clusters of other students. The air was bright and sharp, the sky a hard blue overhead. He pulled out his lunch and set it neatly beside him, making room for the invisible guests that sometimes came to sit with him. Today, a little wind-spirit, shaped like a tumbling leaf, hovered at his elbow, flickering between shades of green. He pretended not to notice, but left a piece of his rice ball on the ground for it. The leaf-thing flickered closer, and he saw it ripple with gratitude, folding around the morsel like a cat curling into the sun.

Izuku watched the other students from a safe distance, their laughter and arguments like something happening on a stage behind glass. He didn’t mind being alone. He had his own world, his own friends. Sometimes, loneliness ached in him, but most days, it was easier to bear than the alternative.

The bell rang, and he gathered his things, careful not to step on the leaf-spirit as he stood. The rest of the day passed in the same thick blur. Lessons, whispers, cold looks, laughter that didn’t belong to him. But he had his notebook, his silent jokes, the flicker of yokai in the corners of his vision. Sometimes, that was all he needed.

When the final bell rang, Izuku slipped out the side door, backpack slung over one shoulder. The city felt different in the afternoon, quieter, the spaces between things growing deeper and stranger. He let his footsteps wander, following the tug of old habits and older friends, the yokai keeping silent pace beside him. For a while, it was enough to just walk, surrounded by secrets only he could see.

It was dusk when Izuku found the yokai in the alley behind the corner bakery. He had only meant to take the long way home, following the faint, humming thread of the world between. His usual escape after a day of being unseen and unwanted by people with normal eyes. But the alley felt wrong. Heavy, stretched thin, a feeling like standing on a cracked sheet of ice and knowing the water was just beneath your feet.

He paused in the mouth of the alley, clutching his bag tight, squinting into the gloom. There, by the trash bins, hunched in the spill of streetlamp light, something barely visible flickered, like the shadow of a moth caught in a spider’s web. Its body was tangled and translucent, every line and edge blurring, colors draining away into nothing. When it tried to move, it winced, the edges of its form breaking apart and curling back, as if the very air was wearing it down.

Izuku’s breath caught. He’d seen fading before. Sometimes a yokai was too weak to stay in the mundane world. Most would wait for the master of the Mononokean, or hide until the end, but this one was too small, too weak. If it disappeared now, it would be gone for good.

He knelt, slow, letting his bag fall to the concrete with a soft thud. The yokai shivered, its eyes barely open, more feeling than form. It couldn’t speak his language, just whimpering, a high-pitched sound that tickled his ears and heart at once.

“Hey. Hey, it’s okay. I see you,” Izuku whispered, voice raw with urgency, pain blooming sharp in his chest. “Don’t go yet, okay?”

The yokai quivered, drifting closer to his outstretched hand, desperate but wary. It was the size of a cat, shaped like something between a fish and a lantern, its body shimmering with a weak, golden light. The cold radiating off of it was intense, making his skin prickle, his breath puff out in thin clouds even though the night was warm.

He glanced around, no humans, no witnesses. No time to lose. He pressed his palm to the ground, offering the yokai a bridge, a thread to hold. “Take what you need,” he whispered. “Please. I’m right here. Just don’t disappear…”

The spirit hesitated only a moment, then flickered against his hand. It was like plunging his arm into freezing water.

Izuku’s arms ached, but he wouldn’t let go. The little yokai pressed close to his chest, its body faint but steadying, each tiny breath like a moth fluttering in his ribs. His heart was pounding, sweat cooling on his neck. He walked fast, head down, winding through alleys where the world thinned, between shrines and silent vending machines.

The city’s hush was alive with yokai. Some peeked from rain gutters, some crouched in the dark beneath old bicycles, some drifted through fence rails like fog. Izuku hurried, desperate, careful not to jostle the fading spirit in his hands. He ducked his head toward a squat, badger-like yokai lounging atop a mailbox.

“Please, have you seen the Mononokean master?” Izuku whispered, voice low, careful.

The badger-yokai cocked its head, wary, then pointed its snout east with a grunt. “There. Try the old train yard,” it rasped, fur bristling, eyes flickering with golden light.

“Thank you!” Izuku gasped, running on.

He pressed forward, following the echoes of places where, just sometimes, he’d glimpsed a presence so strange and deep it made the world feel tilted. A flash of gold, a flicker of smoke, a shape impossible to describe. He’d never gotten close before, he’d always turned away, afraid. But tonight he was desperate. He could feel the spirit in his arms shivering, its small body straining just to hold together.

Another yokai, this one little more than a wriggling ball of mist, floated above a roadside offering. Izuku bowed low, quietly: “The Mononokean master. Have you seen him?”

It twisted in the air, spun once, and pointed a wispy tail toward the old canal bridge. Izuku’s heart kicked, and he followed.

The city’s edges blurred as the sky deepened, pink and purple draining to blue. Then: a turn, a forgotten lane, and suddenly a hush fell so deep it rang in his ears.

He stopped.

A door.

Tall, old, impossibly out of place, stood in a narrow clearing, half-lost between crumbling bricks and wild weeds. Painted foxes, sharp-toothed, eyes bright, twined and leapt across its surface, their forms half-dancing, half-menacing. The air shivered with a warmth and power that made Izuku want to drop to his knees and look away.

Someone stood before the door. He wore a kimono, deep indigo with a golden sash, its sleeves too long, drifting in the faint wind. He was taller than Izuku, shoulders squared, hair pale under the thin streetlight, wild and untamed. For a heartbeat, Izuku was sure he saw a tail flick behind him, or maybe a flicker of animal ears, but then it was gone, the illusion slipping away.

The Mononokean master.

Izuku had never seen him up close before. There was something sharp and fierce about him, a kind of danger, but not cruel. No, it was more like the pressure of an oncoming thunderstorm. His eyes, when they turned, were bright as molten stone and focused wholly on Izuku.

Katsuki was just lowering his hand from the surface of the door, as if he’d only now finished sending someone through. The scent of smoke and distant earth clung to the air.

Izuku froze, clutching the yokai close, throat tight. He almost turned back, habit screaming at him to hide, to run, to disappear, but the spirit in his arms shivered, and Izuku forced his feet forward.

The Mononokean master watched him in silence, the wind shifting his sleeves, his expression unreadable. Foxes stared from the door, their painted eyes sharp.

Izuku stopped just short of the door, bowing deeply, voice trembling. “Please-” he began, then his words caught. He swallowed, holding the little yokai up as proof, his whole body tense and pleading. “Please, I need your help. It’s fading. It needs to go to the underworld. Please…”

The spirit in his arms pressed itself tighter to him, as if it knew. Izuku kept his head low, every muscle in his back ready for rejection or danger. He could feel the Mononokean master’s gaze burning through him, but Katsuki didn’t waste time staring or asking pointless questions when a yokai was fading in front of him.

The door, enormous and strange, waited with the foxes on it almost shimmering in the streetlight, and Izuku stood there holding the trembling, barely-solid spirit out with both hands. Katsuki stepped past him, movements deliberate and unfussy, and slid the painted door open with a sharp tug.

What waited on the other side was pure black, soft, swallowing, like velvet that went on forever. Not cold, not menacing. Just endless, the same nothingness every spirit crossed when leaving one world for the next.

Katsuki squatted down in front of Izuku, meeting the terrified yokai at its own level, his sharp red eyes losing all their edge. His voice, when he spoke, was nothing like the rumors, low and solid and utterly sure. “You’re alright. You don’t have to be scared. Nobody’s going to hurt you in there,” he said, gently coaxing the little spirit from Izuku’s arms.

The yokai shivered, eyes huge, and then turned to look at Izuku for reassurance. Izuku, still frozen with adrenaline, nodded quickly, offering a faint, shaking smile.

Katsuki took the yokai in both hands, careful, cradling it the way you’d hold a rare insect, and rose to his feet. He stepped into the threshold, holding the spirit before him, and dipped his head as if speaking to someone deep in the tunnel. “Take it slow, okay?”

The yokai trembled but pressed forward. Katsuki’s hands guided it gently into the darkness, the blackness swallowing its body bit by bit, until the only thing left was a golden shimmer, then nothing. The spirit slipped into the underworld.

Katsuki stepped back, dusting his hands off, and with a single, practiced movement, slid the great door shut. The moment it clicked into place, the whole thing vanished, leaving only the wind and the sound of distant city traffic. No trace remained except for a small, lingering warmth in the air.

Now there was nothing left between Katsuki and Izuku except empty space. For the first time, Katsuki really looked at him, at the boy standing there with his fists clenched, his face still pale and tense. Katsuki’s gaze was heavier up close, bright and wild and entirely inhuman.

He sized Izuku up, head cocked slightly, something feral and wary in the tilt of his shoulders. “Alright,” he said at last, voice low and rough with suspicion. “Now, why the hell can a human see me? And touch a yokai like that?”

There was no cruelty in his tone, but no kindness either. Just curiosity, and a raw, flickering tension. Katsuki’s eyes narrowed as he waited for an answer, the night suddenly very still.

Izuku’s brain was a mess of panic and embarrassment, mostly panic, but some embarrassment, too, because it was impossible to ignore the way the Mononokean master looked up close. He was striking, sharp angles and wild hair, kimono hanging open at the throat. He wasn’t supposed to be hot. None of the old stories or whispers among yokai ever mentioned that part, but here he was: beautiful, dangerous, and very much not human.

Apparently Izuku had an ideal type and it was Katsuki.

Katsuki circled him, eyes never leaving his face, every step measured. His presence was heavy. Izuku’s heart thundered, his body tense as a trapped rabbit. He tried to shrink in on himself, holding his bag close, not daring to look away. The air felt thicker with every step the yokai took around him.

Katsuki stopped suddenly, so close Izuku could see the gold flecks in his eyes. He sniffed the air, brow furrowing, expression growing more and more annoyed.

“What are you?” Katsuki asked, the words almost a growl. “You smell like a human, but-” He cut himself off, frowning. He didn’t just mean the way Izuku looked or sounded. He could feel it. The air was full of Izuku’s energy. Not just a trickle, but a rolling, crashing tide. Even the strongest of the spirits Katsuki exorcised rarely burned this bright. He bristled, wary but fascinated.

Izuku’s throat bobbed. “I- I’m just a human,” he managed, voice small, wishing he could melt into the asphalt. “I always saw yokai. I didn’t know why. I just wanted to help.” His words tumbled out, desperate not to sound like a threat, or worse, like someone who wanted anything in return.

Katsuki clicked his tongue, circling again, the sleeves of his kimono swaying. He didn’t take his eyes off Izuku, sizing him up like he was some puzzle he hated not understanding. “You have more power than most lower yokai. Hell, more than half the middle ones. You got any clue what happens if the wrong thing gets a whiff of you?”

Izuku shook his head quickly, hair flopping in his eyes, wishing the world would swallow him. “No. I just- I just want to help them. I know I’m not supposed to… see. I try not to draw attention.” He glanced away, heat crawling up his neck.

Katsuki grunted, looking him up and down, almost offended by Izuku’s entire existence. “You’re either a dumbass, or you’re nuts.” But his tone had shifted. There was a grudging kind of respect behind the words, like he couldn’t decide if he wanted to yell or laugh.

Izuku risked another look up, feeling the pressure of the other’s gaze like claws at his chest. It wasn’t lost on him how easily Katsuki could end him right here, but instead the yokai just stared, frown deepening, as if the answer might just fall out of Izuku’s mouth if he stared hard enough.

Silence hung between them. The city seemed to hush, as if every yokai in the neighborhood was holding its breath. Izuku barely dared to breathe himself.

And still, all he could think, half delirious, half mortified, was:

Why does the master of the Mononokean have to look like that?

Katsuki kept circling, his steps slow and silent, the alley shrinking with every pass. Izuku’s skin prickled where Katsuki’s gaze settled, where the sleeves of the kimono brushed his shoulder, where deft fingers tapped his wrist, his jaw, as if confirming he was real. The touches weren’t gentle, but they weren’t cruel, either; more like someone testing a new tool, or poking a wild animal to see if it’d bite.

Izuku stood perfectly still, hardly daring to breathe. The spiritual pressure pouring off Katsuki was dizzying, heavier than anything he’d ever felt. He could smell something wild and burnt cedar. Katsuki’s face gave nothing away, sharp and unreadable.

“Lift your hands,” Katsuki ordered, voice flat.

Izuku obeyed without thinking. Katsuki pressed his fingers to Izuku’s palm, tracing the lines, then squeezed his wrist, as if searching for something just under the skin. Energy thrummed between them, hot and almost electric. Izuku shivered, afraid, but mostly confused.

Katsuki finally stepped back, exhaling through his nose. He crossed his arms, eyes narrowing, considering. The silence stretched, full of things that didn’t need to be said. Finally, his lips twisted into a scowl.

“Fine,” he said. “I’ve decided.”

Izuku blinked, mind scrambling to keep up. “Decided… what?”

Katsuki jerked his chin at him. “You’re going to be my employee.”

Izuku’s heart nearly stopped. “What?”

“Employee,” Katsuki repeated, enunciating each syllable like he was talking to someone who barely spoke Japanese. “You’re gonna work for me. I don’t care what you are. You’ve got enough energy to power half the underworld, and if you’re wandering around like this, some asshole’s gonna eat you. So you’re mine. I’ll put you to work. Got it?”

He didn’t wait for an answer, just glared, as if daring Izuku to argue. “If you’re that determined to help yokai, you’ll help them under me. Otherwise you’ll get yourself, or someone else, killed. Understood?”

Izuku’s head spun, his mouth dry. But deep down, under the shock, a small, burning hope flickered, a chance to really belong in the world he loved most.

He swallowed. “Yes. I understand.”

Katsuki grunted, satisfied, and finally let a hint of a smile show, sharp and wild as anything else about him. “Good. Don’t make me regret it, human.”

Katsuki didn’t bother with explanations. He just turned on his heel and said, “Mononokean. Come.”

Izuku didn’t even have time to ask what that meant before something shifted in the alley behind them. The cracked concrete trembled underfoot. And where there had been nothing but moss-covered bricks and rotting trash bins a moment ago, now stood an old temple door, short and worn and heavy-looking, wedged into a wall that absolutely had not been there before.

Katsuki slid the door open with one hand, revealing not darkness this time, but a room impossibly bright and clean: A traditional tearoom with sliding paper walls and tatami mats that had no business existing in the alley. It was huge inside, far bigger than what the doorframe should have allowed. Izuku blinked, stunned, but Katsuki was already inside.

“Don’t stand there like a dumbass. You’re mine now. Keep up,” Katsuki snapped over his shoulder.

Izuku ducked low, stepping through. The second his foot hit the tatami, the air changed. Warmth rolled over his skin, steady and alive. This wasn’t just a room. It was breathing. Watching. Feeling. There was something enormous wrapped around every wall, in the floorboards, behind the paper panels. Something vast and ancient and utterly aware.

He stood frozen for a moment, eyes scanning the space. It was pristine. The kind of place where noise felt like blasphemy. A low table rested in the center, empty except for a single, massive scroll hanging from an alcove above it. The scroll was blank, until ink bloomed onto the paper in a flowing, elegant script right in front of Izuku’s eyes.

“Who is this?” it read.

Izuku jumped, eyes wide. He stared at the scroll, mouth dry. Katsuki didn’t look surprised. He walked over, kicking off his sandals and dropping into a squat beside the table.

“New hire,” he said. “Human. Don’t throw a fit.”

More text appeared, deliberate and measured. “A human in this room? That’s never happened.”

Katsuki smirked. “You gettin’ shy all of a sudden?”

Izuku stepped closer, his voice barely a whisper. “Is that… it? The Mononokean?”

Katsuki’s grin widened just slightly, sharp teeth flashing. “That,” he said, gesturing broadly to the walls, the ceiling, the floor, “is the Mononokean. You’re standing in it. It’s a yokai.”

Izuku’s breath caught. His knees went weak.

“It’s a living being,” Katsuki continued. “Been around longer than most of the spirits you’ve ever met. Thinks it’s better than the rest of us. Usually right.”

The scroll’s text shifted again. “Rude. But accurate.”

Katsuki rolled his eyes. “It talks through the scroll. It can see, hear, probably judge everything you’re doing, so don’t get weird.”

Izuku swallowed hard. “It’s… alive.”

“Yeah, you already said that. You slow?” Katsuki leaned back on one hand, relaxed but watching him carefully. “You get to live in the real world with this shit now, so you better keep up. The Mononokean’s how we open doors. Move yokai. Cross over. It lets me do the job.”

Izuku stared around the room again, seeing it differently now. The calm wasn’t just calm. It was the steady breathing of something ancient. The warmth wasn’t decor, it was body heat. He was standing inside a yokai.

The scroll flickered again. “He has strong energy. You were right to bring him.”

“Yeah, no shit,” Katsuki muttered, then looked directly at Izuku.

“Give me your address,” he said, sharp and impatient like the conversation had already dragged five minutes too long.

Izuku blinked. “Huh? Oh- right.” He gave it, stumbling over the street name once, flinching like the Mononokean itself might judge him for bad enunciation.

Katsuki turned toward the scroll hanging from the alcove. “Mononokean,” he said, loud and firm, “send him home.”

The scroll didn’t move. The ink didn’t stir.

Then, after a long pause:

“…He’s going already?”

Katsuki narrowed his eyes. “Don’t start.”

A beat.

“He just got here…”

Izuku stared. Did that line curve at the end like it was pouting?

“I live here, not him,” Katsuki snapped. “He’ll be back tomorrow. He’s not getting out of it. Door. Now.”

The scroll hesitated again, then added, slowly

“He feels… nice.”

Izuku flushed to the tips of his ears. “Um.”

Katsuki didn’t look amused. “Congratulations, human. You made the house catch feelings.”

There was a soft, almost bashful rustle in the walls. The air warmed slightly, like the room had sighed.

The doorway finally shifted.

Katsuki waving him towards it. “Go before it changes its mind.”

Izuku nodded and crouched, ducking through the narrow space.

Suddenly he was standing in the entryway of his house. His exact house. His backpack still slung on one shoulder. Everything quiet. Normal.

He turned, heart thudding, and saw the same sliding panel he’d stepped through. It looked perfectly mundane. The faintest warmth still lingered around the edge. He reached out and gently closed it.

Stared.

Closing the front door.

Stared more.

Then opened it again.

The street.

No Mononokean. No tearoom. No glowing passage. Just quiet pavement and the soft flicker of a streetlight buzzing overhead.

Izuku stood there a long moment.

Then he pulled the door shut again and turned around. “I’m home,” he called, his voice oddly hoarse.

“Welcome back, sweetie!” his mom called cheerfully from the kitchen.

The room was quiet. Not peaceful quiet, anticipatory quiet. The kind of silence that followed Katsuki around like a cat that knew he hated it but still wanted to curl up in his lap anyway.

He stood in the center of the Mononokean, arms crossed, jaw tight. The air still smelled like the human boy, Izuku. Not strong anymore, but just enough to linger. That warm, stupid scent like sweat and chalk dust and spiritual energy so thick you could wring it out of his hoodie.

The scroll in the alcove twitched once.

Then again.

Then words appeared with deliberate, syrupy sweetness:

“You hired him~”

Katsuki didn’t even blink. “I didn’t hire him. I prevented a disaster.”

“You hired him.”

“He was gonna die if I didn’t do something!”

“You let him into me. ”

Katsuki’s eye twitched.

“You talked to him.”

“I talk to a lot of yokai. It’s part of the job.”

“You called him a dumbass. That’s your version of affection.”

Katsuki groaned and dropped onto the tatami in front of the table like gravity gave up on him. He flopped dramatically, legs spread out, arms folded behind his head. “You’re being annoying.”

The scroll rustled again, clearly thrilled.

“You’ve never accepted an employee before.”

“I didn’t accept him,” Katsuki muttered. “I claimed him before someone else could snap him up and gut him.”

“Hizashi will lose his mind. You didn’t even look at his last three candidates. You threatened to bite the one with the folder.”

“He deserved it.”

The scroll paused.

“But Izuku-”

“Stop saying his name like that.”

“- Izuku gets to stroll in bleeding spirit like a broken teapot and suddenly you’re all ‘stay close’ and ‘you work for me now’~”

Katsuki sat up, scowling hard. “I wasn’t nice. I told him he’d get eaten. I told him he’s mine. That’s threatening.”

The Mononokean wrote slowly, smugly.

“I like him.”

“You like every fluffy spirit that sparkles when it talks.”

“ You like him. ”

Katsuki growled, dragging both hands through his hair and flopping back again like the floor would swallow him.

“I hate you,” he muttered at the ceiling.

The scroll fluttered softly.

“(｡♥‿♥｡)”

Katsuki stared up at the beams of the ceiling, the edges of his ears red, the tip of his tail twitching under his robe. He would not admit anything. Especially not to it.

But damn if he wasn’t already thinking about what the nerd was doing now.

And if he’d be stupid enough to get possessed again before tomorrow.

Chapter Text

The next day started like every other. Groggy, too early, and full of things that made more sense to other people.

Izuku sat cross-legged at the kitchen table, sleep still clinging to his eyes, staring vaguely at his rice while his mother chattered about something he wasn’t really listening to. Then, like muscle memory, he turned toward her, leaned forward, and carefully plucked a soft, flat yokai off her upper back, this one shaped like a steamed bun with legs, burrowed into her shoulder like a parasite.

“Ugh, there you are,” Izuku muttered under his breath, squinting at it as it tried to crawl up his sleeve.

His mother sighed with sudden relief and stretched her arm. “Oh, that was weird. I must’ve slept funny again.”

“Yeah, must’ve been,” he said with a tired smile, cupping the squirming spirit in one hand and heading to the balcony. The little thing squeaked when he opened his fingers, probably tumbling back into the drainpipe it came from. He didn't ask questions. As long as it didn’t attach to her again.

School was the same stale soup it always was.

The teachers talked like they were teaching by script. The students ignored him when they weren’t whispering about him. Izuku sat through class after class, staring at nothing while a small whiskery yokai clung to the blackboard like a wet rag, barely awake. He doodled spirals in the margins of his notebook, tossed the occasional glance at a passing spirit, and said nothing to anyone.

He liked it better that way.

It was only when the final bell rang that something cracked through the monotony.

He was the last one packing up, slinging his bag over one shoulder, half-shuffling toward the door. His hand slid the panel open, and-

Katsuki.

Kneeling at a low table inside the Mononokean’s tearoom, one hand propped against his knee, the other holding a cup of tea. Still in his kimono. Still very much not supposed to be behind the door of Class 1-B.

Katsuki looked up, completely unimpressed. “Took you long enough.”

Izuku made a noise between a yelp and a strangled wheeze and slammed the door shut with both hands.

The classroom went quiet.

He turned slowly, aware of several people staring now. Someone near the back raised an eyebrow.

“…Did you just freak out at the hallway?” one kid asked, snickering. “Is the ghost of homework haunting us or something?”

“Or maybe Creepyku finally snapped,” someone else muttered.

Izuku ignored them, his face burning, his heart galloping like a startled cat. He turned back to the sliding door and hesitated. Two classmates of his, not bullies but compliant, throwing him weird looks, snickering to each other. They opened the door and just vanished, right as they were about to enter the Mononokean.

The Mononokean only showed itself to those who could see it. And Katsuki? He didn’t even react as students walked towards him and vanished, still sipping tea with an expression that could’ve been boredom or pure irritation.

Izuku stared, wide-eyed, then glanced over his shoulder at the last few students still lingering. They didn’t notice anything strange.

He stepped forward, heart thumping, and slipped through the doorway.

Warm light washed over his skin. The smell of tatami and incense replaced the school’s antiseptic stink. And just like that, he was standing in the middle of the tearoom again.

The air settled around him, like something had taken a deep breath. The door clicked quietly shut behind him. All sounds of the human world cut off.

Katsuki glanced up from the table, one eyebrow arched. “You done being dramatic, or are you gonna piss yourself on the floor next time too?”

Izuku exhaled. “Why are you here?!”

“I work here,” Katsuki deadpanned, sipping his tea again. “And now so do you. Get used to weird door placements.”

Izuku wasn’t sure if he was dizzy from the transition or just his new life. Either way, he dropped his bag at the wall and sat down with a quiet thud, still staring at the door that was, just a minute ago, his classroom’s exit.

Izuku didn’t expect the Mononokean to… talk back.

Well, not like a person. Not with a voice. But as soon as he settled into the same spot as yesterday, on the left side of the low table, his hands neatly folded in his lap like some kind of weird new-hire etiquette was required, the scroll hanging in the alcove started flickering again.

Not stern calligraphy like before.

But soft, bouncy strokes.

“(◕‿◕) Welcome back, Izuku!”

Izuku blinked. Then stared.

The next line formed in a gentle swoop of ink.

“I’m so happy you came again. Did you sleep well?”

Katsuki’s teacup hit the saucer with a sharp clink.

“No,” he muttered. “Nope. Don’t even start.”

Izuku didn’t hear him. He was already leaning toward the scroll, eyes wide with awe. “You remembered my name?”

“Of course! I remember everything about you (⁄ ⁄•⁄ω⁄•⁄ ⁄)♡”

Katsuki groaned. “I hate this.”

Izuku couldn’t stop the smile that spread across his face. It wasn’t fake. It wasn’t the polite mask he used at school. This was real, wide and alive, the kind he only had around yokai.

“You’re so… friendly,” he said.

“I like you! You’re warm. Your energy feels like sunlight through windows. Very soft! I want you to stay forever!”

Katsuki threw his hands in the air and stood. “No. No staying forever. He’s not furniture.”

Izuku covered his mouth to stop the laugh. This place, this yokai, wasn’t just powerful and ancient. It was… cute . And chatty. And weirdly clingy in a way that made Izuku’s chest ache with comfort.

Katsuki flopped back down with the kind of defeated grunt that said this had already gone too far. “You’re making it worse.”

Izuku leaned his elbows on the table. “So… how do I start helping?”

The scroll answered before Katsuki could.

“First, you sit and drink tea. Then you get a job. Simple! We work together now! (＾▽＾)/”

Izuku grinned. “Sounds perfect.”

Katsuki slumped back like he’d aged ten years. “I should’ve just hired a damn spirit.”

Then he went to get tea.

Izuku sat cross-legged on the tatami, fingers resting gently on the table, and the scroll bobbed a little in its alcove, exuberant, if a piece of ancient parchment attached to a living spirit-room could even be called that.

“You’re more relaxed today (´｡• ᵕ •｡`) ♡”

Izuku chuckled, tilting his head. “I guess I am. You made it easy.”

“You’re very easy to talk to. Your energy’s calm.”

They kept going like that, exchanging silly comments and questions about one another. The Mononokean’s scroll danced with kaomojis and little scribbles.

Izuku leaned in, curious. “So do you ever leave the room?”

“Nope. This is my body. I live here. If I left, all the walls would fall down! I don’t want that.”

“Right… yeah, let’s not have that.”

The moment was warm. Too warm.

Because right then, Katsuki kicked the door open with his foot, one hand holding a tray with two cups and a third already half-drained in his other. His eyes scanned the room, catching the way Izuku was smiling like he’d found a best friend and a puppy all at once.

He scowled immediately.

“Of course you’re getting along.” He stomped over, set the tray on the table with zero grace, and slammed a cup in front of Izuku hard enough for it to rattle.

“Thanks?” Izuku offered, a bit startled.

“Don’t get cute. You’re still my employee, dumbass.”

Katsuki dropped into a crouch, draining the rest of his own cup in one go, then set it down with a heavy clack and stared straight at Izuku.

“We got a job.”

Izuku sat up straighter.

“Old yokai. Pretty powerful type. Been hanging around a temple for decades,” Katsuki said, reaching into his sleeve and pulling out a thin strip of folded paper, tossing it across the table. “Wants to pass on to the underworld.”

Izuku nodded slowly, unfolding the paper. It held only one line of kanji, brushed thick and heavy in an old style.

“But?” he asked, knowing there was more.

Katsuki’s scowl deepened. “But he says he won’t go until he finds something he lost. Some keepsake. Memory or item, I don’t know- he’s not exactly forthcoming.”

“He’s very old,” the scroll added, “and kind of a hoarder. His memories are tangled like yarnballs (¬_¬)”

Katsuki jabbed a finger at the scroll. “You’re not helping.”

“I can help,” Izuku said quickly, glancing between them. “We just have to figure out what it is, right?”

Katsuki groaned under his breath. “Yeah. Guess we’ll start with his shrine. He’s waiting.”

“I’ll make a fresh door ( ˘ ³˘)♥”

Izuku glanced at the scroll, heart already thudding.

Katsuki stood up, already annoyed again. “Come on, dumbass. Time to work.”

The Mononokean door opened with a soft shiff , like nothing more than a breeze catching paper. Revealing a moss-covered path behind it, trees loomed above, thick and old, their branches sagging with time and weather. A half-forgotten shrine crouched at the top of worn stone steps, hidden from the world by creeping vines.

Izuku stepped through after Katsuki, the ground soft under his shoes, air cooler than it should’ve been.

Katsuki cracked his neck, scanned the trees, then raised his voice like a bark. “Oi, show yourself. We’re not gonna stand around all day.”

Silence stretched for an uncomfortable minute. Then came a low, distant rumble, like the shuffling of clouds or an ancient thing rousing from sleep. The wind shifted, leaves pulling in one direction.

Izuku’s breath caught as something massive slipped into view from behind the shrine’s arch.

A yokai. Long and winding. It floated, coiling lazily through the air like a ribbon in water. Its body was smooth and eel-like, dull silver mottled with age, marked with faded ceremonial patterns that curved across its length like old tattoos. It must’ve been twenty meters long, but it moved with the unbothered pace of someone who’d long stopped caring about time.

Its face was rounded, with wide, tired eyes and little whiskers, and as it drew closer, Izuku couldn’t help but think it looked weirdly... cute .

The yokai huffed, voice crackling like dry leaves. “Took you long enough.”

“You didn’t answer the first five times I called,” Katsuki snapped. “Be glad I didn’t leave.”

The yokai snorted, weaving around a tree with lazy grace. “Hmph. Didn’t expect the Mononokean’s new master to be a brat.”

“Didn’t expect an elder to be this damn slow.” Katsuki crossed his arms, clearly unimpressed. “You said you needed something before you’d go to the underworld. What the hell is it?”

The yokai drifted in a thoughtful loop around a stone lantern, sighing like the weight of the question itself was a chore. “It’s a ring. A small one. Gold, I think. Been buried here a long time. A woman lost it. Long ago. She used to sweep the grounds. Always humming. She cried when it went missing. Didn’t know I was watching. So I kept it safe.”

Izuku blinked, leaning forward. “You’re staying here just to give it back?”

The yokai scoffed. “Well, she never came back for it. Thought maybe I could pass it on. Seemed right. It’s not mine. But I liked her.”

Katsuki muttered under his breath, already walking the edge of the shrine, muttering about sentimental spirits and how he wasn’t a damn treasure hunter.

Izuku stayed where he was, staring up at the yokai, something tugging at his memory. The way it moved. The sound of its sighs. The curve of its voice when it said “hmph.” There was something familiar there, something buried under years of growing up.

Then it hit him.

Izuku’s head snapped up. “Wait... You’re Kageshima!”

The yokai paused, blinking slowly. “...What?”

Izuku took a step closer, heart racing. “You used to hide behind the shrine roof when I was little! You’d knock leaves off trees to spook birds. I called you ‘eel-gramps.’ You scared the hell out of my kindergarten friends.”

The yokai stared. Then narrowed his eyes.

“…Little human brat who used to leave apple peels at the gate.”

“That was me!”

A long pause.

Then the yokai's whiskers twitched. “Well I’ll be… You got tall.”

“You got huge!” Izuku grinned, practically glowing now. “I didn’t even recognize you!”

“I didn’t recognize you either, beanpole.”

They both laughed. Or at least, Izuku laughed, and the yokai let out a creaky hohoho like a boat settling into dock. His coils slowed, loosening, drifting comfortably around the shrine steps.

Kageshima’s long body shifted. Not fast, not aggressive, just deliberate and slow, like someone returning to an old habit. The ancient yokai floated down, his huge body curling gently around Izuku from behind. Not crushing or tight, more like… a soft coil of protection. A hug, if you ignored the fact that it felt like being wrapped by a semi-truck.

Izuku froze for a moment, then relaxed with a quiet laugh, hands brushing the cool, smooth scales at his sides. “Still clingy.”

“Hmph,” Kageshima snorted, gruff. “You’re just small. Easier to contain than listen to you yap.”

“You’re cuddling me.”

“I’m containing you.”

Katsuki stood a few feet away, arms crossed, expression flat. “The fuck is this, nap time? We’re here to work.”

Izuku straightened, a little sheepish as Kageshima’s coils lazily unwound. “Right. Sorry.”

Katsuki pointed toward the shrine grounds like he was commanding a military op. “Find the damn ring, dumbass. It’s somewhere in this overgrown dump.”

So they searched.

And searched.

And searched .

Izuku combed through old offering bowls, gently lifted mossy stones, sifted through piles of long-rotted leaves. He even reached into the hollow of an old cedar tree, elbow-deep, hoping something would click. Nothing.

Katsuki swept his way across the shrine like an angry bloodhound, growling curses every time he turned over a rock and didn’t find gold. “It’s the size of a coin, how the fuck has it not rusted into oblivion? Why would anyone stay behind for this ?”

Izuku paused to wipe sweat from his temple, fingers brushing against something soft, a patch of old cloth tangled in the roots of a camellia bush. No ring, just damp earth.

Hours passed. The sun shifted. Kageshima drifted lazily above, pretending not to care.

Until Katsuki snapped.

“You’re stalling your moving for a damn trinket!” he barked, kicking at a pile of old gravel. “You realize that?! You could’ve been sipping spiritual sake in the underworld by now!”

Izuku looked up from the patch of earth he’d been kneeling in. He wasn’t annoyed anymore. Just… thoughtful.

He turned, brushing dirt from his hands, eyes narrowing as he studied Kageshima.

“You said a woman lost it,” Izuku said slowly, carefully. “A woman who swept the shrine. You kept it for her.”

Kageshima’s tail flicked in a lazy loop, but his face didn’t change.

“You remembered that for years. You don’t even care about the ring itself, do you?” Izuku’s voice softened. “You just want to give it back to her.”

Kageshima blinked once. Slowly.

Then looked away with a huff. “Tch. Don’t get romantic.”

“Gramps…” Izuku stepped forward, smiling with something gentle, something heavy. “It was her wedding ring, wasn’t it?”

Kageshima turned his head slightly, mouth pulling into a tiny, reluctant scowl.

Izuku’s eyes widened. “She was your wife.”

Silence.

Katsuki stopped mid-step, glancing over his shoulder.

“You were human once,” Izuku breathed. “And she still is.”

Kageshima growled, low and almost petulant. “So what? So what if I was? What’s it matter now?”

“It matters,” Izuku said quietly. “You waited all this time. You didn’t stay behind for a ring. You stayed for her.”

Kageshima didn’t answer. Just snorted again, slower this time, the curve of his body settling lower, looser.

He didn’t deny it.

Katsuki didn’t say a word for a long moment. Just stared at Kageshima’s huge, slow-blinking eyes, then down at the moss-covered ground like it personally offended him.

He grunted. Not angry this time, just irritated.

“…You could’ve just said it was for your wife,” he muttered, kneeling beside a half-collapsed stone lantern. “Would’ve saved me hours of flipping goddamn rocks.”

“You never asked nicely,” Kageshima replied, too quickly, then immediately huffed and floated upward like he hadn’t said anything at all.

Katsuki growled under his breath but didn’t argue. He just went back to searching, a little more focused now, a little more careful. His hands didn’t smack things out of the way this time, they shifted branches aside, scraped dirt slowly.

Izuku, on the other hand, was buzzing. His spine straightened, this wasn’t just a ring lost in the dirt. This was a promise. Something that had lasted through lifetime, through a human becoming a yokai after death.

He scoured the area behind the shrine, fingers parting through leaves and mulch, reaching under the warped edges of a wooden donation box half-swallowed by the earth. And then-

His hand closed on something hard and smooth.

He sat up slowly, dirt-streaked fingers uncurling.

There, gleaming quietly in the light through the trees, was a ring.

No rust. No cracks. Just aged gold, softened by time and wear. It was simple, just a small rounded band with a single, worn mark where a tiny stone once sat. But it was beautiful in a way nothing else they’d touched today had been.

Izuku held it up, voice tight. “Found it.”

Kageshima didn’t come swooping over, didn’t gasp or cry. He stayed coiled high in the tree branches, face turned ever-so-slightly away.

“I didn’t think it’d still be here,” he said roughly. “I figured it… sank. Or got taken.”

Izuku smiled up at him.

The old yokai made a noise, half scoff, half exhale, and his long body twisted down in slow spirals. His eyes were wet. He blinked hard.

“Tch. Dust. Lotta dust in this forest.”

Katsuki rolled his eyes but didn’t say anything, just crossed his arms.

Kageshima hovered near the ring, staring at it for a long, long time. Then: “We’re going to her.”

Izuku blinked. “What?”

“She’s alive. Not too far. I want to see her get it back,” he said, eyes fierce now, voice steady. “Doesn’t matter if she can’t see me. You’ll give it to her. I’ll just… watch.”

Katsuki looked skeptical. “How far is ‘not too far?’”

Kageshima turned in the air, already floating toward the tree line. “Short walk.”

“Bullshit,” Katsuki muttered immediately, striding after him.

And yeah, ten minutes in, as they climbed what was definitely a mountain trail, with gnarled roots and uneven paths, Izuku sweating and Katsuki silently grinding his teeth, it became very clear that short was the biggest lie Kageshima had told all day.

They walked for an hour.

A full, goddamn hour.

Katsuki was one twisted ankle away from vaporizing someone, probably Kageshima, whose long winding body slithered lazily above the path like a parade float.

Izuku was panting by the thirty-minute mark, wiping sweat off his face with his sleeve, shoes thudding against steep dirt steps that seemed to regenerate in front of them.

“You know,” Katsuki growled, barely disguising his rage, “we have the Mononokean. It opens portals. Instant travel. Literal space folding. And yet we’re walking. Like idiots.”

“I told you,” Kageshima rumbled from above, his tone smug and infuriatingly nostalgic, “this was a short walk in my day. I walked twice this to school every morning. Barefoot.”

Izuku didn’t have the breath to join the argument. His legs were jelly, but the ring in his pocket kept him moving. Each time it clinked against his phone.

Eventually the forest broke, revealing a quiet mountain town tucked into a green slope, roofs weathered and low, smoke curling from a few old chimneys. It was peaceful, simple.

Kageshima slowed, weaving lower, gaze fixed on the house at the farthest edge.

That one was different.

Modest, like the rest, but with a small, cared-for shrine just outside the gate. The kind of shrine a person cleaned with their own hands every morning. Fresh food rested in a bowl: a small onigiri, pickled plum, a cup of hot tea that hadn’t even gone cold yet.

Izuku stared, heart stuttering.

“She really still-”

“Every day,” Kageshima said, voice low. “She talks to me, even now.”

Izuku swallowed hard, fingers brushing the ring in his pocket.

“How do I… give it to her?” he asked quietly. “I mean. She’s not gonna see you. But I don’t want her to think I’m some freak showing up with her dead husband’s ring in the middle of her garden-”

“Just do it,” Katsuki grunted. “Humans react how they want. It’s not your job to explain the world to them.”

Izuku didn’t get more time to panic.

The front door creaked open and an old woman stepped out onto the porch with a small broom. Her spine was bent, but her face was sharp and clear . Her gray hair was tied back, her yukata loose and clean.

She blinked once at Izuku standing stiff in her yard. Then her eyes narrowed. “And what , may I ask, are you doing in my garden, young man?”

Izuku stammered, frozen. “I-! I- I have something- I didn’t mean to- uh-” He reached into his pocket, yanked the ring out, and blurted, “Your husband sent me!”

The silence was nuclear.

Katsuki pinched the bridge of his nose.

Kageshima hovered like a guilty dog above the porch, body curled gently around her without touching her, his long face still and unreadable.

Izuku braced for it, for the yelling, the disbelief, the get out of my yard , or what kind of prank is this , or maybe just her calling the police.

But the old woman stared at the ring.

Stared a long time.

Then she let out a breathless, wheezing laugh .

“Oh, of course he did,” she chuckled, stepping forward with shaky hands. She took the ring, eyes shining, and cradled it against her chest like something sacred. “That stupid, stubborn man.”

She slipped it onto her finger, next to a thinner, older band. They fit like they’d never been apart.

“I told him not to worry about it. I said it was just a ring,” she whispered, smiling through tears. “But he never listened.”

Izuku blinked, stunned.

The woman reached up and wiped her cheeks with her sleeve, smiling softly. “He always waited too long to say things. Always did things on his own time. But he came through in the end.”

Izuku smiled slowly, warmth flooding his chest, because right then, just behind her, Kageshima was curling around her porch rail like a snake. He tucked his chin near her shoulder, his long body looping through the beams and steps, watching her with a look so full of peace it hurt.

She didn’t see it.

Didn’t feel it.

Kageshima lowered himself more, curling tighter around the woman like a shawl. His coils snaked around the porch beams, folding delicately between the old wood without creaking. His large head hovered just behind her, resting near her shoulder, and he whispered things she couldn’t hear.

“I love you,” he said, voice low and raw. “You old woman… I never said it enough. But I love you. You were everything.”

She hummed softly to herself, eyes on the ring still shining faint gold against her skin.

“I’ll wait for you,” Kageshima went on, his massive frame tucking in around her like a nest. “If you ever make it to the underworld, if the stars let you turn yokai- I’ll find you. I will.”

Izuku didn’t even try to hide the tears anymore.

He bit the inside of his cheek, blinking hard, heart wrung out. He’d seen a lot of yokai. A lot of kindness. But this… this was love. Old, stubborn, undying love.

Kageshima whispered again, softer this time. “You made me more than human. And my love will do that to you too.”

And the woman, still humming to herself, turned back into the house briefly, then returned with a wrapped cloth bundle and shoved it into Izuku’s arms without hesitation.

“Here,” she said briskly. “You look like a stick. Eat. Don’t argue.”

Izuku blinked. “I- thank you-”

“Go. Whoever sent you, thank him. And tell him to stop being dramatic.”

Izuku barely managed a nod, his arms full of warm cloth and food, as she waved him off with a smile and turned back toward her altar.

They walked in silence for a while after that.

Katsuki didn’t rush. He didn’t complain either, for once. Just led them through forest paths until they reached a clearing. A perfect spot for a gate.

Katsuki rolled his shoulders and raised his hand. The air pulsed.

The fox-marked sliding door shimmered into existence out of nowhere, golden paper flickering under the dappled light. Katsuki didn’t say anything. Just stepped aside, arms crossed.

Kageshima hovered quietly at the threshold, coiling one last time around Izuku.

“You were a good kid,” he said. “You still are. Don’t forget that.”

Then he pulled him close, giving one last squeeze.

“Thank you,” Kageshima murmured.

Izuku smiled, eyes wet again. “Say hi to the other yokai for me.”

The old man gave a short, choked huff, half laugh, half sob, and then slid smoothly through the door.

Gone.

Katsuki let the silence sit a beat longer, then dragged the door shut in one motion. It vanished into the clearing like it had never been there.

“Mononokean,” he muttered.

A shimmer.

The tearoom door appeared in the trees like it had always been part of the bark and shadows.

Izuku followed quietly, bundle of food in his arms.

Back inside, the air was warm again, the familiar soft light washing the tension out of his shoulders. He placed the food bundle on the table gently, unwrapping the top.

Rice balls. Grilled fish. Pickled vegetables. Still warm.

He smiled faintly and took one of the smaller pieces, some kind of mochi, and carried it to the alcove.

“For you,” Izuku said softly, placing the food just beneath it.

The scroll twitched slightly. Then:

“(⁄ ⁄•⁄ω⁄•⁄ ⁄)♡ Thank you, Izuku~”

Izuku didn’t get to cry for long.

He sat at the low table, wiping at his eyes with the sleeve of his school uniform, trying to keep the food from getting soggy with the saltwater dripping down his cheeks. His nose sniffled. His chest was tight. But his smile was wide and warm and completely helpless.

It was too much to explain. Too much for words to wrap around. Just… beautiful.

His first job.

A lifetime folded into the hands of an old woman and the silence of a yokai’s final thanks. Izuku wouldn’t forget it. Not ever.

“(｡♥‿♥｡) You did so well, Izuku~!” came the swish of ink across the scroll.

Izuku laughed, voice cracking a bit. “Thanks. I feel like I barely did anything.”

He rubbed his face again, trying to clean up whatever emotional mess had taken over, and then finally let himself slump forward against the table, head against his arm.

“I could get used to this,” he mumbled.

“You better. I already picked a cushion for you ( ｡•̀ ᴗ-)✧”

Katsuki groaned from the other side of the room, where he was pacing with the kind of intensity that suggested he wanted to punch something purely on principle.

“I leave for two seconds,” he barked, “and you’re over here weeping and flirting with a damn wall.”

“It’s not flirting!” Izuku squeaked.

“It absolutely is~ (≖‿≖)”

Izuku snorted, sitting up straighter now, pushing his tea toward the middle of the table. “You’re just jealous it likes me more.”

Katsuki spun on his heel. “Jealous? Of what , exactly?”

“The Mononokean likes me.”

“(✿ ♥‿♥) I do~”

Katsuki jabbed a finger at the scroll. “You’re a damn room. You’re supposed to be neutral. ”

“I’m a yokai. I can have favorites. ”

“Bullshit!”

Izuku broke into laughter, finally relaxing fully, leaning into the rhythm of the room. The tearoom was warm again. Peaceful. He reached for one of the rice balls and tore a bite out of it like he hadn’t cried thirty seconds ago.

“This is going to be fun,” he said through a mouthful.

Katsuki flopped onto his cushion like he’d been shot. “I’m gonna regret hiring you.”

“You already do.”

“(＾▽＾) You’re both disasters. I’m so proud.”

Chapter Text

Katsuki sat cross-legged at the low table, brush in hand, eyes fixed on the job report with murderous focus. The rice paper in front of him was already half-filled with elegant strokes, his handwriting crisp and controlled despite the twitch in his jaw and the very visible vein popping near his temple.

He was trying, trying , to write a simple report on the Kageshima job . Just basic procedure. Minimal detail. The kind of clean log any respectable Mononokean master would file.

Too bad he lived in a hell.

Izuku was rolling back and forth on the tatami just a few feet away, making pitiful whining sounds like a bored child stuck in a waiting room.

“There’s gotta be another job by now,” he groaned, legs swinging into the air. “I can feel it in my bones. I was born for this. Let me do something.”

“You did one job,” Katsuki snapped without looking up, brush tapping the inkstone a little harder than necessary. “You think you’re ready to take over the whole fuckin’ yokai network now?”

“Maybe,” Izuku chirped, rolling to his side with a lazy grin. “I mean, I did deliver true love through a golden ring. That’s basically the climax of most novels.”

“(＾◡＾) He was very heroic,” the Mononokean chimed in through the scroll, the strokes of the letters practically bouncing. “He braved the mighty mountain, carried the food bundle, and cried like a noble baby~”

“I did not cry that much,” Izuku muttered into the floor.

“He wept. Sophisticated. ”

Katsuki clenched his teeth, dragging the next line of kanji out harder than necessary.

Izuku rolled back over, lifting his head with a devious sparkle in his eyes. “Hey, Mononokean… should we just get married?”

Katsuki’s hand jerked.

“(⁄ ⁄>⁄ ▽ ⁄<⁄ ⁄) Izuku!! You can’t propose like that!! I need flowers and a nice kimono!!”

Izuku gasped dramatically, clutching his chest. “You’re right. I’ll get the shrine spirits to be our band. Katsuki can be the best man!”

Katsuki dropped his brush.

“I will incinerate both of you,” he said without moving his head.

“Katsuki’s gonna cry at the ceremony~”

“I’M NOT GOING TO-”

Izuku was cackling now, curled in on himself with laughter. “Imagine him trying to give a speech- ‘this is the stupidest union I’ve ever witnessed, but I guess it makes sense because they’re both disasters’-”

“Yes,” Katsuki barked, grabbing for the inkwell before it tipped. “And stop talking, I’m halfway through the fucking paragraph about the ring recovery!”

Izuku rolled over to the table, chin on the edge, grinning up at Katsuki. “You writing down our registry gifts yet? I want a rice cooker and some floating floor cushions.”

“You’re gonna get an exorcism,” Katsuki growled, finally slamming the report closed.

And yet… he didn’t leave.

He sat there, still twitching, lips pressed into a thin line, as Izuku giggled and the Mononokean drew sparkly hearts in the corner of the scroll. Katsuki didn’t stop them.

Surprisingly, Izuku had reception inside the Mononokean.

He stared at his phone like it was a joke, then checked it twice just to be sure. Two bars. Full data. Wi-Fi, even- how? Was the Mononokean secretly hooked into a ghost router?

Didn’t matter.

He quickly typed out a message to his mom:

"Hey! Just a heads-up, I’ll be out late. Everything’s fine. I'm with a new friend :) Don’t worry!"

He knew that smiley face would do nothing to stop the avalanche of questions he was going to face later. Still, she deserved a heads-up. She worried. That was her job.

Izuku sighed, put the phone on mute, and tucked it back into his bag just as the scroll unrolled with curious little flicks.

“What was that???”

Izuku blinked, then smiled. “Oh, that? That’s my phone. It’s like… a tiny screen box that connects me to other people.”

“It talked . Did you trap someone inside it???”

“No!” Izuku laughed. “It’s more like… letters. Magic letters. I can send a message to someone far away and they’ll get it instantly.”

“Σ(・口・) So powerful…”

Izuku pulled it out again and tapped the screen, showing off the icons. “I can also take pictures, play music, look up answers to any question.”

The Mononokean buzzed with curiosity, more text spilling out excitedly.

“I want one!!”

“You… don’t exactly have hands.”

“Details!!”

Izuku was about to explain how charging cables worked when the scroll suddenly jolted, ink shaking into place in urgent, sharp strokes:

“We have a visitor!! From the u nderworld!!”

Katsuki looked up from where he’d been sprawled in the corner, flipping through a ledger.

“Guest?” he muttered, already pushing himself up. “We didn’t request anyone. Who the hell’s barging in?”

Izuku stood too, heart racing. “Are we supposed to get random guests?”

“Usually not.”

The air shifted.

One of the side panels peeled back, slow and soundless, and in slunk a shape low to the ground, small, four-legged, and shimmering faintly with energy. Its movements were cautious, graceful, like it didn’t quite trust the floor.

It was a yokai, but not humanoid. Not tall or sharp or imposing. Just soft.

It looked like a dog. A mutt. Round muzzle, stubby legs, wide ears that drooped a little. Its body was faintly translucent, fur fluffing and thinning with each shaky breath. The tail wagged hesitantly, and its tongue lolled out for a moment before retreating. No words. Just a quiet, anxious panting.

The scroll flickered.

“This one has permission. A low-level yokai with one-day travel rights. Requested a pass to visit the Mundane World.”

“Why?” Katsuki asked, narrowing his eyes.

“...To see his family.”

Izuku’s breath caught. His chest pulled tight.

He stepped forward, kneeling gently so he didn’t startle the creature.

The yokai perked up slightly, padding closer. Its body shivered with emotion, pressing its head against Izuku’s knee, eyes wide and trembling.

Katsuki crossed his arms, sighing. “Of course we get the sappy ones.”

Izuku smiled softly, hand hovering just over the yokai’s head. “You just want to check if they’re okay… if they still remember you.”

The dog-yokai whined, tail wagging once.

Izuku was on the floor. Fully committed. Legs folded under him, arms wrapped around the soft, shimmery body of the yokai.

The creature had all but melted into his lap, tongue out, tail thumping the tatami with slow, sleepy joy. It pressed its nose into Izuku’s chest, paws kneading like a kitten. Izuku giggled, a mess of warmth and sniffling sounds, one hand ruffling the thick fur behind its ears, the other scratching its belly with deep, practiced circles.

“There’s no way anyone could say no to you,” Izuku murmured, voice soft, eyes shining. “You’re too good. You’re perfect.”

The yokai let out a happy little whimper, flipping onto its back entirely with all four paws up like it was demanding full royal treatment. Izuku obliged. Belly scratches were non-negotiable.

Meanwhile, Katsuki leaned over the table, pinching the bridge of his nose as the scroll bobbed beside him, scrawling a calm stream of script.

“His name in life was Maro. Died about eight years ago. He was a mixed breed, very loved, especially by the younger son. They live in a house near the base of Yamamura hill.”

Katsuki grunted, skimming the next lines.

“He doesn’t want to cause trouble. He just wants to see if they’re doing okay. That’s it.”

“Great,” Katsuki muttered, glancing over at the floor where Izuku was now cradling Maro like an infant. “We’re babysitting a ghost dog.”

“He’s offering three yokai jade tokens,” the Mononokean added, ink flowing smoothly. “Rare ones. Good quality.”

Katsuki’s brow rose.

Izuku looked up from the snuggle pile, still half buried in tail fluff. “Is that a lot?”

Katsuki looked sideways at the scroll. “Enough for two jobs, maybe three. Depends on market rate.”

Maro gave a quiet, excited bark and wiggled in Izuku’s arms, licking his chin with an icy tongue that made Izuku squeal and laugh all over again.

Katsuki groaned. “Whatever. Fine. We take him.”

He turned to the scroll, already mentally planning the route. “Tell me exactly where we’re going.”

Maro was glowing.

Not literally, his translucent form remained faint and ghost-light, but emotionally? He was lit up like a festival lantern. Izuku could feel the joy radiating off of him in pulses. The little yokai leapt and twisted in the air, pouncing on Izuku’s legs with giddy barks, his tail a blur of motion.

Izuku laughed, falling backward, letting Maro roll over him like an excited tide. “Okay, okay! You win again! You’ve pinned me seventeen times!”

Maro gave a proud little yip and licked Izuku’s chin with his icy tongue, before flopping dramatically across his chest, panting like a victorious beast.

“I could do this all day,” Izuku muttered, fingers working through the soft shimmer of Maro’s fur. “You’re the best boy. Still the best.”

Eventually, though, it was time.

The Mononokean’s scroll unrolled gently.

“Portal ready. Please be careful~ (｡•̀ᴗ-)✧”

The tearoom walls shivered. One of the sliding doors peeled open to reveal a quiet suburban road.

Katsuki stood near the frame, arms folded. “You’re the one carrying him if he gets distracted.”

“I hope he gets distracted,” Izuku replied, scooping Maro up under his arms and giving him another snuggle before setting him down. “He deserves it.”

To the average person, Izuku looked like a teenager out for a casual evening walk. But in reality, he was accompanied by two yokai, one large, invisible, very grumpy, and in charge; the other a joyful spirit-dog weaving in and out of his legs like they’d never missed a single day.

Izuku didn’t care if he looked crazy.

He’d walk down the middle of the street talking to empty air if it made Maro happy.

They approached the quiet house nestled at the edge of a hill, trees curving protectively around the garden. It was older but well kept, with climbing ivy along the fence and lights still glowing in the windows. Izuku hung back near the treeline, crouching behind a cluster of bushes, heart thudding.

In the yard was a small gravestone. Simple. Tucked neatly beside a tiny shrine. A wooden bowl held fresh water. Next to it, an offering: a dried chew stick.

Maro saw it and sprinted .

He snatched the stick like it was a prize from heaven and collapsed beside the stone, gnawing it furiously with his tail thudding against the grass. Izuku smiled so hard his face hurt.

Then the gate creaked open.

A young man stepped through, tall and lean in a hoodie and joggers, backpack slung over one shoulder. He headed straight into the garden, giving the gravestone a small bow and kneeling beside it. He poured fresh water into the bowl, setting down another stick next to it.

Maro’s ears perked up. The stick dropped from his mouth.

Then he exploded into movement.

He circled the man, barking, jumping, tail wagging so hard his back legs barely touched the ground. He tried to lick his face, to nuzzle his shoulder, to crawl into his lap and be noticed.

Izuku swallowed hard, fingers clenched in the fabric of his jeans.

Katsuki stood behind him, quiet.

The man just laughed, brushing his hair back, oblivious to the yokai zooming around him.

And then-

Another dog trotted out of the house. An Akita puppy, ears perked and eyes bright. It yawned, then spotted Maro.

And froze.

Izuku’s breath caught.

The puppy stared. Its tail wagged once.

Then, without hesitation, it pounced .

They collided in a flurry of movement, legs tumbling, tongues lolling, tails wagging like they were trying to take off into space. Maro yelped in joy. The Akita yipped back, twisting in circles as if it had known him forever. They played like littermates, like soul echoes, biting at air, rolling in the grass, tumbling around the shrine like children reunited.

The young man just laughed, shaking his head. “You got the zoomies already, Maro?” he chuckled. “You’re worse than the old man.”

Izuku blinked fast. Maro. The name.

They’d named the new puppy after him.

And now the two were tearing up the garden together, one living, one long gone, like nothing had changed. Like joy was eternal.

Izuku stayed crouched in the bushes, knees pressed into damp grass, barely daring to breathe too loudly. He didn’t want to ruin it, not for Maro, not for the man who had no idea how close his old friend really was.

Beside him, Katsuki stood with his arms crossed and his back against a tree, silent and watchful. He wasn’t scowling. Not exactly. Just… focused. Stern in a way that felt more like respect than annoyance.

In the yard, the young man pulled a faded tennis ball from his hoodie pocket and gave it a lazy toss.

Both dogs exploded after it.

The Akita barked, all legs and floppy ears, skidding across the grass. Maro blurred like a streak of smoke, just behind, tail wagging so fast it was almost invisible. The ball bounced twice before the Akita pounced on it, then stumbled as Maro nudged it from behind, sending it rolling again. The two danced around each other, snapping playfully, trading off who got to win.

The boy laughed, completely unaware of the glowing outline of joy that trailed just behind his puppy’s shadow.

Weird little movements, ball redirecting mid-air, odd wind gusts, the puppy pouncing too early and somehow still catching it, would have raised eyebrows in another setting. But the Akita’s boundless energy made it all look natural, like he was just that chaotic. Like there was no need to question the impossible.

Katsuki exhaled through his nose. “Tch. Idiots.”

Izuku tilted his head up, still crouched low, and grinned. “Letting him stay this long, huh? You do have a heart.”

Katsuki didn’t look at him. “Shut up.”

“A soft, sentimental one.”

“You wanna get exorcised?”

Izuku snorted into his sleeve, muffling his laugh.

He stayed mostly quiet after that, careful not to draw attention. The kid in the yard never once looked toward the trees, too distracted by the way his dog played like it was the happiest animal on the planet. And maybe it was.

Maro rolled in the grass, tongue lolling, tail wagging, his spirit-body shimmering like morning dew in sunlight. The Akita yipped and headbutted him, both of them tumbling until Maro got the ball and pranced around like he’d won the world.

Izuku watched it all, eyes full of light, whispering just loud enough for Katsuki to hear.

“Bet he dreams of this every night.”

Katsuki’s eyes narrowed, but his voice was lower this time. “Yeah. That’s why I let him stay.”

The young man finally scooped the Akita puppy into his arms, its tongue lolling, tail flicking weakly in sleepy circles, and headed back inside, leaving the garden behind in a hush of rustling leaves and kicked-up grass. The back door clicked shut behind him.

Maro hesitated only a second before following. His paws didn’t press into the earth. They never had. He glided in, barely brushing the surface, quiet as memory, slipping through the door behind his favorite human like he had never left.

Izuku remained crouched near the treeline, hands tucked under his knees, heart still full from the scene. He didn’t move. Didn’t even speak. Katsuki stood beside him, arms crossed, quiet and unmoving.

Minutes passed.

Then the back door creaked open again, just a crack, and a curl of light slipped out into the garden.

Maro bounded through it like a comet. His tongue lolled, his tail whipped, his body all fluid joy. He practically launched across the yard, a blur of shimmer and affection, and made a beeline straight for Izuku.

“Wait- Wait- Maro-!”

Too late.

The spirit dog leapt into Izuku’s arms at full tilt, sending the boy stumbling back onto his rear with a breathless oomph , grass flying. Izuku burst into laughter, arms wrapping around the furry weight pressing into his chest. Maro’s tail thumped against his side like a war drum.

“You’re heavy!” Izuku gasped, still laughing as he pushed himself up. “You don’t look this heavy, but you are!”

Maro licked his cheek once, then settled his head against Izuku’s shoulder with a soft, ghostly huff.

Izuku grinned and shifted his stance, lifting the yokai into his arms with effort. Maro wasn’t exactly small, but Izuku didn’t care. He’d carry him all the way back if he had to.

Katsuki rolled his eyes but didn’t argue, just turned toward the wooded path leading back to where the Mononokean’s door waited. The faint outline of the sliding panel shimmered into view up ahead.

“Let’s go,” Katsuki muttered. “Time’s almost up.”

Izuku followed, careful with his steps, holding Maro close against his chest. The dog yokai nuzzled under his chin, content and exhausted. His energy flickered slightly, softening now, calm. Like whatever weight he’d carried for eight years had finally been lifted.

Izuku pressed his cheek against the fur, whispering just for him, “We’ll take you home now, okay?”

Maro didn’t respond. He just thumped his tail once and snuggled in deeper.

The Mononokean door sighed open into that warm, golden room that somehow smelled like tatami, old paper.

Izuku crouched low, ducking through the portal, Maro still cradled in his arms like a worn, beloved stuffed animal. Katsuki followed last, sliding the door shut behind them with a quiet clack that sealed them off from the outside world.

The moment they were inside, Maro wriggled free, gently, politely, and flopped onto his side right in the middle of the tearoom. His tail thumped against the floor in soft, slow beats, paws twitching lazily as he stretched out with a huff.

Izuku dropped down beside him, eyes already damp.

“I know,” he whispered, “it’s not goodbye forever, but…”

Maro rolled over, offering his belly like it was sacred ground.

Izuku obliged, fingers working through soft, wispy fur with practiced affection. He scratched under Maro’s chin, behind his ears, under his foreleg, until the spirit-dog's back legs kicked weakly in the air, tail wagging in lazy arcs. There was no sadness in Maro’s eyes. Only contentment. That kind of soft, glowy happiness that came from something finally complete.

“You’re the best boy,” Izuku murmured, voice cracking just a little. “You did so good.”

Maro gave a slow, wagging nod, then nudged his nose under Izuku’s hand one last time before rolling upright again.

With a soft chuff, he trotted over to the low table, where he reached under the tuft of fur at his neck and pulled out a tiny cloth bag, barely the size of Katsuki’s fist. He set it down with a delicate tap.

The scroll twitched, writing already curling onto the paper.

“Payment. Three jade tokens, exactly as promised. High-grade spiritual seal.”

Katsuki raised an eyebrow. “Huh. Didn’t expect a dog to carry proper contract shit.”

“Maro is very responsible ( ´ ▽ ` )ﾉ”

Izuku wiped his eyes quickly and smiled.

Maro turned to face them one last time. His ears perked, his tail swished. He padded over to Izuku, nuzzled his chest one final time, then licked his hand with that soft, cold tongue.

“Take care,” Izuku whispered, fingers tightening just slightly in his fur.

Maro let out one last quiet bark, then padded toward the Mononokean’s door as it opened silently, this time revealing a calm, silver fog just beyond the frame.

He paused at the threshold, looked back once, and then scurried inside.

The door slid shut behind him.

It was late. The kind of late where the streetlights buzzed faintly and the world beyond the paper walls of the Mononokean had gone quiet. The soft hum of the room dimmed to a warm lull, shadows long, cushions sunken in from the day’s use.

Izuku stood by the door, backpack slung loosely over one shoulder, blinking sleepily as he tucked his phone back into his pocket. He yawned, eyes glassy from exhaustion, but still smiling, tired, content, and buzzing on the lingering warmth of what they'd just done.

Katsuki sighed, already gesturing.

The Mononokean opened the portal again with a faint creak of paper, sliding one panel aside to reveal Izuku’s front entryway.

Izuku rubbed at his eyes, then turned and grinned at the scroll hanging beside the alcove.

“See you tomorrow?” he asked.

“(≧◡≦) You better come back! I already miss you!!”

Katsuki rolled his eyes, mumbling about sappy idiots.

Izuku stepped through and vanished, the door sliding shut behind him with a soft click.

Silence fell over the room again.

But it didn’t last long.

Ink already forming on the scroll, quick strokes that jabbed at Katsuki’s nerves before he could sit back down.

“So.”

Katsuki grunted. “No.”

“So~~~”

“No.”

“You like him.”

“He’s loud.”

“You’re blushing~”

Katsuki pointed a finger at the scroll like it had personally insulted his bloodline. “I will set you on fire.”

“(・∀・) Worth it.”

The Mononokean paused for a moment. Then more carefully:

“He would lay down his life for a yokai.”

Katsuki didn’t reply right away. He leaned back on one hand, rubbing at his neck with the other. His mouth pressed into a flat line.

“Yeah,” he muttered eventually. “He would.”

“That’s dangerous.”

“Yep.”

The scroll fluttered slightly, more solemn now.

“But kind of… comforting too. That someone like him is the one who can see us.”

Katsuki closed his eyes briefly, then opened them again, gaze hard on the empty space where the door had been.

“It’d be worse if it were someone else,” he admitted. “Someone greedy. Or scared. Or power-hungry.”

“He just wants to help.”

Katsuki snorted. “Dumbass.”

“Your dumbass~”

“I will burn this room down.”

“I’ll tell him you said that~”

Katsuki growled but didn’t get up.

He stayed there, staring at the spot where Izuku had disappeared, arms crossed tight, but not nearly tight enough to hide the faint, reluctant smirk tugging at the corner of his mouth.

Izuku barely had time to kick off his shoes before his mother called out from the kitchen.

“Welcome home, sweetie!” Her voice was cheery, but there was a sharp curiosity laced underneath it. “Did you eat already? I made miso, but it’s fine if you’re full.”

“Yeah,” Izuku said quickly, toeing his sneakers into the corner. “I- I had some food. A friend gave me something.”

He winced the second the words left his mouth.

Sure enough, Inko Midoriya appeared around the doorway within seconds, eyes wide and shining, holding a dishtowel in both hands like she needed it to brace herself.

“Ah yes, a friend?” she repeated.

Izuku froze halfway through unzipping his hoodie. “…Yes?”

“A new friend?” she echoed, advancing slowly like he might spook and flee. “You mean, like… a person? Your age?”

“Mom-”

“Is it a girl? A boy?” she gasped. “Is it Haru again?! Oh Izuku, is he being nice now??”

“No!” Izuku said quickly, waving his arms. “I mean yes- he’s a boy! But no, it’s not Haru! It’s- Uh. Someone else.”

Inko blinked. “So, you met someone new?”

He nodded, tugging his hoodie the rest of the way off and trying to avoid eye contact.

She stared at him for a long moment, then smiled, warm and gentle but impossibly knowing. “That’s wonderful, honey.”

Izuku scratched the back of his neck. “Y-Yeah… He’s kind of intense. But… nice. In his own way.”

She sat at the table, drying her hands, gaze never leaving him. “You haven’t had a friend since…” She trailed off for a beat. “Since the kids at school stopped inviting you places.”

Izuku flinched but nodded. “Yeah.”

“So…” She tilted her head. “Tell me more.”

“Well…” He paused. “His name’s Katsuki. He wears traditional clothes a lot. Lives kind of… secluded. But he’s smart. A bit older than me. Kind of rough around the edges, but he has this weird sense of responsibility.”

She perked up. “Traditional? Like kimono-traditional?”

“Yeah. You could say he’s really into… heritage.”

Inko’s eyes sparkled. “Ooohhh. He sounds handsome.”

Izuku flushed, tugging at his sleeves. “That’s not- Anyway, I met him through helping someone. Kind of like a part-time thing.”

“What do you help with?”

“Just… helping people get where they need to go. Deliveries. That kind of thing.” He smiled awkwardly. “It’s… fulfilling.”

She leaned forward. “Do you think you’ll see him again?”

“Yeah,” Izuku said before he could think. “Tomorrow, actually.”

She beamed. “That’s so lovely, Izuku.”

He nodded, heart warm and heavy. “Yeah… It is.”

Because technically? Nothing he said was a lie.

And thankfully, Katsuki had a human form. So he didn’t had to invent a brand new human on the spot.

Izuku yawned and rubbed his eyes. “I’m gonna shower and head to bed.”

“Alright,” Inko said gently, watching him with a soft look. “I’m really glad, Izuku.”

He gave her a tired, grateful smile, and padded off to his room.

Chapter Text

It didn’t take long for a new rhythm to settle into Izuku’s life.

At first, it had been charming. A little whimsical. The Mononokean’s door appearing tucked into a side alley behind the school gym? A surprise, sure, but magical.

Then it started getting weird.

One morning, Izuku opened his locker and stared directly into the Mononokean’s tearoom.

Another time, he reached to grab a snack from a vending machine, and the compartment door peeled open like a sliding panel, revealing Katsuki seated at the low table, sipping tea like it was the most natural thing in the world.

But the worst, the worst, was the toilet.

He'd been mid-day, mid-class bathroom break, minding his own business, when he opened the stall door… and found himself face to face with Katsuki, standing in the middle of the Mononokean tearoom like he'd been waiting specifically for this.

“-GAH!” Izuku screamed, stumbling back and smacking into the stall wall. “Katsuki?! What- Why- How?!”

“You’re the one taking ten minutes to piss,” Katsuki muttered, stepping aside and motioning him in like he was inconveniencing him.

“I thought there were rules about privacy!”

“Yeah. And I don’t care.”

Izuku groaned, dragging his hands down his face, and stepped into the tearoom-slash-restroom doorway with all the dignity he could salvage.

From there, the jobs came one after another.

Most were simple: Deliver a message, escort a yokai through a passage, retrieve an item left in the mundane world. Occasionally, there were trickier ones, restless spirits who needed help locating objects tied to their form, or stubborn yokai who wouldn’t leave without being talked down.

Katsuki handled the heavy lifting. Izuku handled the talking.

“Another job well done! You’re getting so good at this, Izuku~ (｡♥‿♥｡)”

“You say that every time,” Katsuki muttered.

“Because it’s true~”

Katsuki didn’t comment, but he did refill Izuku’s tea cup without being asked. That was something.

And every day, like clockwork, the Mononokean opened a quiet, hidden door back to Izuku’s house, slipping him through before the evening crowd could notice a teenager materializing out of thin air near the residential blocks.

He’d barely be in the door when it started.

“Welcome home!” his mom called from the kitchen. “Did you see your friend again today?”

“Hi, Mom. Yes. I mean- Yes, I saw him.”

“Oh good!” Her head popped around the corner, eyes bright. “Did he say anything new? What’s his favorite color?”

“… He doesn’t really do small talk,” Izuku said, slipping off his shoes.

“Does he have friends? Does he like rice crackers? What’s his job again?”

“I told you. Deliveries.”

“You sure it’s not a shrine job? He sounds very spiritual. Does he bathe?”

“Moooom,” Izuku groaned, already halfway to his room.

“I’m just saying! He’s your first real friend in years, I’d like to know what I’m working with!”

Izuku closed the door behind him, flopped face-first onto his bed, and muffled a tired but very real smile into his pillow.

Because yeah, this was his life now.

Weird, unpredictable, exhausting.

And kind of perfect.

Izuku shoved his arms through his blazer sleeves, still brushing sleep from his eyes as he stepped into the hall.

“Do you have your lunch?” his mother called from the kitchen, trotting after him with the practiced urgency of every school morning.

“Got it!” Izuku called back, adjusting his bag on his shoulder, already reaching for the door handle.

Inko caught up to him just before he opened it, eyes twinkling, hair tied up in a casual messy bun. “So… Katsuki-kun.”

He paused. “Huh?”

She leaned in like she was sharing a sacred secret. “You never told me what kind of tea he likes. I was thinking, if he’s ever nearby, you could invite him in.”

“Ah- Uh-”

“You know I don’t mind your friends coming over,” she added with a smile. “I can make snacks!”

Izuku laughed nervously. “He’s… really not the type to do home visits.”

“Still. Maybe sometime? Just to say hello?”

“Mmhmm- Okaygottagotoloveyoubye-”

He yanked the door open-

And stopped cold.

It wasn’t the street.
Not the sidewalk.
Not the hedge or mailbox or neighbor’s cat licking its paw across the road.

It was tatami. And the golden light of the Mononokean’s tearoom, floating just beyond the frame like it had been waiting for him all morning.

Izuku blinked hard, trying not to jerk backward.

“Oh?” Inko leaned slightly to the side, peeking around him. “What are you staring at?”

“Uh- Just- Just forgot something,” Izuku blurted, stepping halfway into the doorway with his back blocking most of the view. Not that it mattered anyway. “Sorry, I’ll grab it on the way out!”

Inko squinted. “Is Katsuki already waiting for you?”

Izuku’s throat closed.

“M-Maybe.”

“Ohhh,” she hummed. “Then you must bring him by sometime. You know how nosy the neighbors are. If I tell them my son’s got a friend who looks like a Heian-era actor, they’ll riot.”

Izuku laughed way too loudly. “Yup! Totally! Bye!”

And with that, he stepped through the doorway and slammed it shut behind him with a sharp clack.

“Where’s Katsuki?” he asked aloud, tossing his bag toward a corner cushion, shoulders slumping.

The scroll didn’t answer.

He turned around-

And saw the door frame rattle.

A tall figure stood just behind it. Very still. Very quiet.

Izuku’s soul briefly attempted to leave his body.

Because Katsuki was there. And he was pissed.

His eye twitched. One hand lifted slowly from where it had been gripping the side of the frame. The other was rubbing a bright red spot on the bridge of his nose.

“You slammed the fuckin’ door into my face,” he growled, voice low and vibrating with the kind of wrath that suggested someone was about to be forcibly exorcised.

Izuku’s brain short-circuited.

“I didn’t know you were- !”

“I called out, you dumbass!”

“I thought that was a bird- !”

“That was your name! In full syllables!”

Izuku took a step back, raising both hands. “You’re very stealthy in the mornings, okay?! Like- Like a cursed ninja!”

Katsuki stomped into the room, fists clenched, murder in his eyes. “I oughta put a bell on your goddamn shoes so I hear you ring every time you take a step.”

“Wouldn’t that make you more annoyed?”

Katsuki paused. Scowled deeper.

The scroll finally twitched.

“He looked really cute slamming the door though~ (≧∇≦)/”

“Shut UP.” Katsuki snapped at the wall.

Izuku tried. Gods above, he tried.

He clamped a hand over his mouth, teeth digging into his knuckle, throat convulsing with the effort to not laugh out loud. But the Mononokean’s teasing messages wouldn’t stop. The scroll was fluttering beside him, practically vibrating with amusement, little kaomojis and cheeky comments tumbling down it like a waterfall.

“(๑˃ᴗ˂)ﻭ He said your full name~”
“(⁄ ⁄•⁄ω⁄•⁄ ⁄) So  domestic!!”

Izuku’s face turned red. Deep red. Neck-to-ears red.

His shoulders trembled as he tried to hold in the laugh. The wheeze that slipped out sounded like a squeaky toy was suffocating him.

Katsuki’s eyes narrowed.

“You think this is funny?” he growled, slow and lethal, like a predator scenting fresh blood.

Izuku’s shoulders trembled harder. “I-” he gasped behind his palm, “I’m so- So sorry, I really am, but- Pffftt- ”

That was it. Game over.

The laugh broke out of him in an ungraceful, full-body wheeze. He crumpled to his knees, chest heaving, clutching his gut as the Mononokean proudly flashed another:

“＼(≧▽≦)／ Izuku has crashed~”

“Oh for fuck’s sake-” Katsuki growled, and then-

He pounced.

Not with a dramatic yell or some performative threat. No, Katsuki just moved , fast and smooth and all muscle, and suddenly Izuku was on his back with a firm weight straddling his hips and a death glare inches from his face.

Izuku froze.

Oh no.

OH no .

His laughter strangled itself in his throat. He blinked up at Katsuki, wide-eyed, chest still hiccupping from the laughter, but now for a completely different reason.

Katsuki’s knees pinned him in place. His hands were braced on either side of Izuku’s head, veins in his arms flexing with tension. His face was flushed, just a little, maybe from anger, maybe not, but his eyes were sharp, dangerous.

His canines were showing.

He was gorgeous.

And Izuku’s brain helpfully offered one word:

“Fuuuuuck.”

Katsuki stared down at him, scowl still present, but flickering with something unreadable.

“You done?” he asked, voice low and too close.

Izuku’s breath caught.

Was he done?

Absolutely not.

But his mouth was dry and his heart was hammering in places it had no business hammering.

“I- Uh- M-Maybe?” he croaked.

Katsuki’s eyes narrowed, searching his face for… something. The tension in his arms didn’t loosen. If anything, he leaned down a little closer, hot breath brushing across Izuku’s cheek.

“You got a death wish, showing your throat like that,” he muttered, voice like gravel and fire.

Izuku swallowed.

The scroll fluttered wildly with little animated kaomojis and a fresh burst of teasing text that Izuku refused to read. His entire body was locked in a state of sweaty panic under Katsuki’s hips, and something was definitely happening that had nothing to do with spiritual energy and everything to do with heat and pressure and the way Katsuki was hovering over him.

Izuku’s brain was melting. He could feel the flush crawling down his neck, his chest. Worse, he could feel the heat pooling sout, way south, and there was no saving it. Not unless Katsuki suddenly decided to vanish in a puff of smoke and leave him to die quietly of shame in the corner.

And of course, Katsuki wasn’t budging.

His eyes narrowed just a bit, catching the tremble in Izuku’s hands, the tight way he pressed his knees together-

“Oh my god,” Izuku wheezed under his breath

Before Katsuki could definitely ask what the hell he meant, the door rattled.

Both of them froze.

A single, polite knock echoed across the tearoom.

“Scheduled client here! Letting them in~ ♡”

Katsuki shot up like he’d been scalded, the air practically crackling as he shoved to his feet with a scowl and stormed to the doorway.

Izuku scrambled to the side, dragging a cushion over his lap with the stealth of a panicked raccoon, internally thanking every ancestor and minor kami he could think of.

The sliding door eased open, and a yokai stepped into the tearoom, small-framed, hunched slightly, draped in a long scarf that covered most of his body. His eyes were round, glinting silver, and he had six tiny floating spirits bobbing around him like sleepy balloons. Little ones, extremely little, each the size of a plum, with translucent fur and twitchy ears.

“Apologies for the intrusion,” the client said, bowing low. “I have… some trouble.”

Katsuki folded his arms. “I remember. You said you weren’t ready to go yet.”

“I’m not,” the yokai confirmed. “I’ve taken up residence near an old temple. But lately, smaller yokais have been drawn to me. They’re harmless, but they’re causing issues in the area. Knocking over offerings. Disturbing the shrine wards. People have started thinking the place is haunted.”

Katsuki grunted. “And?”

“They need guidance,” the yokai said simply.

Izuku finally sat up straighter, cushion still casually draped across his lap. “So you’re not asking to exorcise them. Just… help.”

The yokai nodded.

“I can do that,” Katsuki muttered. “But we’ll need to make sure they’re not tethered to anything that’ll snap when we move them.”

The client bowed again. “I would be deeply grateful.”

One of the tiny spirits floated near Izuku and gave a sleepy chirp, its little tail curling like a question mark.

Izuku’s heart melted.

Yeah. This beat dying of embarrassment any day.

The shrine was tucked between ancient cypress trees on the slope of a wooded hill, a cobbled path winding up like an old memory worn into the earth. Lanterns lined the approach, stone guardians flanking the stairway, their surfaces worn smooth from decades of quiet offerings and reverent hands.

Izuku stood just past the torii gate, looking up in open awe.

“...This is his shrine?” he asked, eyes tracing the arching rooflines, the clean sweep of the main hall’s architecture, and the fresh-cut flowers.

The yokai, who still hadn’t offered a name, only a bow, gave a simple nod. His six tiny tagalongs swirled around him like drifting fireflies.

“Damn,” Izuku whispered.

The shrine was in impeccable condition. The paint hadn’t chipped. The wood was oiled and warm under the early sun. There were offerings laid with care, packaged snacks, rice balls wrapped in cloth, small toys and coins, a folded letter written in a child’s scrawl. This wasn’t some forgotten, moss-choked corner of a rural town. This was actively cared for.

Katsuki stood beside him, arms crossed, eyes scanning the structure. “This one’s on the verge,” he said bluntly.

“On the verge of what?” Izuku glanced at him.

“Becoming a minor kami,” Katsuki muttered, already stepping toward the main hall. “Give it another few years of this shit, devotion, upkeep, a strong enough emotional tether, and he’ll transition. Yokai to kami.”

The yokai didn’t react. His eyes were calm. Humble.

Izuku turned back to the offerings and the shrine’s gentle energy, the subtle hum of presence so full it made the hair on his arms lift.

“But… he still asked for help?” Izuku asked.

“He’s still a yokai right now,” Katsuki said. “He doesn’t get the authority and strength of a kami until he completes the change. And until then, he’s stuck cleaning up after the ones who flock to his power like moths.”

The tiny yokai orbiting their client chirped again, soft and shrill like wind chimes.

Izuku crouched, extending a hand. One of them floated near his palm, nudging him.

“They don’t seem malicious,” he murmured.

“They’re harmless,” their client confirmed, voice soft but steady. “They sensed safety here. Shelter. That’s all. But they keep tripping the wards. Scaring off visitors. Making a mess.”

Katsuki exhaled. “We’ll sort it. They’re not bound to anything here?”

“Not yet.”

“Then we move them. Somewhere safe. Somewhere they won’t cling to you too hard and slow your transition.”

Izuku blinked. “Transition?”

Katsuki glanced at him. “You can’t become a kami with unstable yokai latched onto your back. You think the spirits in shrines just happen to be clean and contained?”

Izuku looked back at the six little ones, now tangled gently in his sleeves, cooing, one of them suckling on the strap of his backpack, and bit back a fond smile. “You’re telling me these guys are a problem?”

“They’re cute,” Katsuki said. “And like any cute thing, they shit everywhere if you don’t train ‘em.”

Izuku looked to their client. “You ready to say goodbye?”

The yokai didn’t smile. But he gave a small, respectful nod.

“They’ve had enough time with me,” he said, voice a touch heavy. “It’s time they move on.”

Izuku gathered the small spirits one by one, each barely resisting, maybe sensing it wasn’t an ending, but a beginning. He stepped through the Mononokean’s door with the little ones curled close to his chest like glowing embers, their light soft and sleepy.

Katsuki followed behind, silent, gaze lingering one last time on the shrine.

Because he could feel it too.

That old yokai? He’d be a kami by next spring.

Chapter Text

The moment they stepped back into the Mononokean, the tearoom glowed with a low, restful warmth. Izuku dropped to the floor with a soft thud, the tiny spirits still clinging to him like oversized fluffballs with zero sense of boundaries. One perched on his head. Two were snuggled into his chest like kittens. One was chewing on the corner of his shirt, which Izuku gently pulled out of its mouth, only for it to start gnawing on his finger instead.

He laughed. “You guys are hopeless.”

Katsuki stood nearby, arms crossed, watching the scene with narrowed eyes. Not out of irritation, well, maybe a little irritation, but mostly focus.

“They’re too weak to be exorcised alone,” he said flatly, stepping around Izuku and kneeling beside the scroll alcove.

“(｡•́︿•̀｡) They're babies…!” the Mononokean agreed, scrawling out the thought dramatically. “It’s like yeeting newborns into a tornado!”

Izuku flinched. “Yeeting?!”

“You get the picture!”

Katsuki grunted. “The mundane world’s too dangerous. They’ll get pulled into crap they can’t handle. They can’t latch to another yokai without risking codependence.”

Izuku, slowly trying to remove a spirit now curling inside his collar, tilted his head. “So what do we do?”

Katsuki stared at the little wriggling fluffballs. Then made a decision.

“There’s a place in the underworld.”

Izuku froze.

Katsuki continued like he hadn’t just casually dropped a bomb. “A nursery, kind of. A yokai runs it. Keeps the small ones in check until they’re ready to hold form. It’s off-grid, stable. Quiet.”

The Mononokean scrawled excitedly:

“Auntie Nurai’s Home for Half-Formed Babies !! ♡~”

“That is not the official name,” Katsuki snapped.

“It should be~ (＾▽＾)”

Izuku’s fingers tightened on the fluffball now purring in his lap. “So we bring them there?”

Katsuki nodded. “We escort them.”

Izuku blinked. “You mean I’m going into the underworld?”

Katsuki’s eyes didn’t waver. “Yeah.”

The room felt heavier all of a sudden. Not in a bad way, just weighty. Serious. Like the tearoom itself recognized the shift.

“Izuku,” the Mononokean began writing, slower this time, “Do not let anyone know that you are a human.”

Izuku nodded. “I figured.”

Katsuki’s voice was low now. “You have to lie. You keep your head down. Don’t say anything unless I say it’s safe. Most of ‘em won’t be able to tell, but if any of the big ones find out you’re human, we’ll have a headache on our hands.”

Izuku swallowed.

Then looked down at the tiny spirit pawing at his knee.

Then nodded. “Okay.”

The Mononokean, touched and in full chaotic-parent mode, practically burst into action. The scroll whipped out a fresh sheet and immediately began writing a full field trip packet.

“Rules for Izuku: Underworld Edition!”
“Rule 1: Don’t talk unless Katsuki talks first!”
“Rule 2: Don’t wander! That place is huge! ”
“Rule 3: No screaming or doing anything that screams ‘HUMAN!’”
“Rule 4: Keep your spiritual energy contained!! You’re practically a goddamn spotlight!!”
“Rule 5: Look cool. Be mysterious. Everyone loves a quiet, brooding type!”
“Rule 6: Don’t eat anything purple.”

“Wait what?” Izuku blinked.

Katsuki groaned. “Don’t ask. Just don’t.”

Izuku looked at the spirits still tangled around his body, chirping and snoozing and clinging like little life rafts.

And then he smiled.

The fabric hit his shoulders with a rough fwump.

“Put that on,” Katsuki said, not waiting for a reply as he tightened the loose robe around Izuku’s torso, tugging the folds over the telltale collar of his school uniform. “You stick out like a sore thumb.”

Izuku fumbled to tie the sash awkwardly while trying not to dislodge the tiny yokai nestled all over him. One had wrapped itself around his neck like a scarf, warm and softly purring. Another nuzzled under the flap of his new robe, mouth gently nibbling the edge of his sleeve like it was some sacred chew toy. The rest curled against his chest and arms, like clinging to him was their job.

“Y-You sure they’ll be okay like this?” Izuku asked, one hand bracing the smallest spirit on his shoulder, the other fixing the oversized sleeves threatening to swallow his hands.

“They’re half-asleep and fused to your aura like burdock,” Katsuki grunted. “They’re not going anywhere.”

The scroll near the alcove gave one last warning scribble:

“GOOD LUCK SWEETIES~ Don’t DIE!!! ⊂(・﹏・⊂)”

Then the door creaked open.

Golden light spilled from the frame, but not the gentle warmth of the Mononokean. This was sharp, hot, and alive. The buzz of distant voices filtered through, layered and strange. The smell of incense. Sweet smoke. Wet stone and dry air.

Izuku took a deep breath and followed Katsuki through.

What greeted them was a wide, bustling street, sun-drenched, lined with low wooden buildings and shop stalls that looked like they’d been pulled straight from the Edo period. Painted signs creaked overhead. Paper lanterns swung in the wind. There were no cars. No wires. No signs of the modern world.

But there were yokai everywhere.

Some floated, wisp-bodied and long-limbed. Others scuttled, crawled, or strutted like they owned the damn street. A massive turtle yokai with legs like tree stumps sunned itself beside a tea shop. A woman with a translucent kimono and eyes like ink balanced a tray of snacks with five arms. Yokai children, ran giggling barefoot down the street, their forms ranging between furred, scaled, and spectral.

The Underworld didn’t feel dead. It felt ancient. Alive in a way the human world couldn’t be. Like everything here pulsed with energy.

Izuku’s breath hitched.

Katsuki shot him a side-eye. “Don’t gawp.”

“I’m not-”

“You’re gawping. Close your mouth.”

Izuku did. Swallowed hard.

The baby yokai shifted against him, responding to the ambient energy. A few stirred, blinking sleepy little eyes, but none tried to leave his arms.

“Alright,” Katsuki muttered. “Stick close.”

They walked.

No one stared. That was the strange part for Izuku. Despite the dozen reasons Izuku thought he’d be outed instantly, his clothes, his very humanness, the yokai around them barely blinked. They just flowed around Katsuki like he belonged here.

Because he did. Katsuki was a yokai after all.

Izuku kept his head down, letting his bangs shadow his face. He moved with purpose, mimicking Katsuki’s stride, doing his best impression of “quiet, mysterious attendant.” The robe helped, soft, old fabric with faint embroidery at the edges.

The deeper they went, the more the street opened up, into bridges, small canals, and floating torii gates that shimmered in the air. Somewhere nearby, music played, sounds of plucked strings, slow drums. A trail of smoke drifted skyward from an open shrine.

Izuku breathed in slowly.

And under the layers of heat and incense-

He felt home.

Izuku didn’t realize he was smiling until his cheeks started to hurt.

The underworld wasn’t cold or dark or filled with screaming like old stories said. There weren’t rivers of the dead or bone piles or clawed monsters dragging souls off to be judged. It was a town. A vibrant, weird, incredible town. Edo Japan, but different. If Edo Japan had floating koi lanterns and buildings that sometimes shifted slightly when you walked past. The smells were richer, the colors deeper, the air thick with something that buzzed under the skin in a way that wasn’t unpleasant.

And nobody looked at him like he didn’t belong.

No whispers. No stares. No suspicious glances at the human in their midst, because no one knew.

His borrowed haori marked him as Mononokean staff. The distinct stitch pattern across the hem glimmered faintly and some sort of rank indicator he didn’t fully understand yet. But yokai glanced at it, then looked away respectfully. Some even nodded. A few even bowed.

And Katsuki, walking just ahead of him with his usual scowl and don’t-fuck-with-me energy. It was like walking behind a wrecking ball. Pathways cleared. The yokai practically folded themselves out of his way without a sound.

It helped.

A lot.

Izuku adjusted the sleeping baby in the crook of his arm, then gently patted the others still curled against his ribs and shoulders. “Still with me, little guys?”

A tiny squeak answered from inside his sleeve, followed by a nuzzle.

“Okay, that’s a yes,” he mumbled fondly.

He fell into step beside Katsuki, a little closer now, still watching the streets but starting to relax into the rhythm of it all. The stone paths were smooth beneath his sandals. The buildings had the warm, crooked lean of age, and yokai moved around them with a casualness that felt absurdly normal.

Izuku leaned slightly closer.

“…So this is it?” he whispered. “The underworld?”

Katsuki grunted. “Yeah.”

Izuku looked around again, like he might’ve missed something. “It’s... normal.”

Katsuki gave him a sideways glance. “What were you expecting?”

“I don’t know. Fire? Screaming? Chains? Lava?”

Katsuki snorted. “This isn’t hell, dumbass. It’s just the yokai world. We’re not dead.”

“Yeah, I got that now.” Izuku smiled again, adjusting his grip on one of the fluffballs. “It’s actually kind of... beautiful.”

“Tch,” Katsuki didn’t argue.

They passed a floating stall selling strange noodles that writhed in their bowls and a paper merchant whose wares blinked at them from the shelves. Music played somewhere close, a three-stringed shamisen mixed with deep drums that made Izuku’s ribs vibrate.

And through all of it, no fear. No loneliness he was so used to in the mundane world. No side-eyes or whispers like back home.

He didn’t have to talk to anyone. He didn’t have to explain himself.

He was just here. With a job. A purpose.

A soft voice cooed beside his ear. One of the smallest spirits curled deeper into his collar, sighing like a napping kitten. He smiled down at them, letting his fingers brush over their tiny forms like stroking feathers.

Maybe he couldn’t say he was human.

Maybe he had to lie, and stay hidden, and pretend.

But for the first time in his life?

Izuku Midoriya didn’t feel like an outsider.

The further they walked, the quieter it became.

The bustling streets faded behind them, swallowed by the sound of cicadas and the whisper of tall grass swaying in the breeze. The path narrowed into a dirt trail, lined with rice fields on one side and gentle rolling hills on the other. A few butterflies drifted lazily past. Izuku adjusted his arms, careful not to jostle the baby yokai too much, not that they minded. Most of them had gone full ragdoll, legs and ears limp, their tiny bodies soaking up his warmth like sleepy little sunbathers.

Katsuki said nothing as they walked, but Izuku didn’t mind. The silence here was peaceful. Heavy in a comforting way. Like the world didn’t need words to feel full.

It wasn’t long before the shape of a building appeared in the distance. At first glance, it looked like a normal countryside farmhouse. Plain wood siding, a tiled roof weathered by time. There were rows of vegetables planted neatly beside it, a small orchard behind the fence, and even a chicken-like yokai strutting around in the yard like it owned the place.

But the closer they got, the more the details came into focus.

There were wind chimes hanging everywhere, dozens of them, each one glowing faintly, their sounds soft and oddly melodic. Little paper charms flapped from the eaves. A carved sign hung over the door, handwritten in a bubbly script:

“Yokai Nursery - Auntie Nurai”

Izuku blinked. “It really is a daycare…”

The yard confirmed it.

Small yokai of all shapes and sizes wandered freely, fuzzy ones, floaty ones, some shaped like objects, one that looked suspiciously like a tiny stove with eyes. A few were playing with wooden toys. One was trying to eat a daikon root half its size. There was even a slide.

A yokai slide.

Its tongue was the slide.

Izuku tried not to laugh.

The front door opened before they could knock.

A tall yokai stepped out, humanoid, but with skin like bark and eyes like pools of golden sap. Her hair was long, braided with flowers that didn’t wilt. She wore a long apron, and her hands were stained with flour.

“Auntie Nurai,” Katsuki muttered with a nod.

The yokai woman lit up at the sight of him. “Katsuki! Well, don’t you look pissier than usual, come here, let me see that pretty face.” She reached up, pinching his cheek like he was a toddler.

“Tch- Get off me!” Katsuki hissed, jerking away.

Nurai laughed, then turned her gaze to Izuku. Her eyes narrowed for a moment, but not in suspicion, just careful observation.

“And this must be your new assistant,” she said warmly, smile softening. “You brought someone for me?”

Izuku bowed slightly, the movement a bit clumsy with five yokai still clinging to him. “Yes, ma’am. They need a safe place to grow.”

“Well.” Her voice gentled even more. “You’ve brought them to the right place.”

She stepped forward and extended her hands. The little ones reacted immediately, noses twitching, eyes peeking open. A few shifted, hesitating, then floated into her arms like she was gravity itself.

“I’ll take good care of them,” she promised. “They’ll be loved here.”

Izuku exhaled, tension he didn’t know he was carrying slipping from his shoulders. He gave each one a soft goodbye pat as they floated free, though one needed a little extra convincing before it let go of his sleeve.

“Thank you,” he murmured.

Then Nurai looked at him again.

And smiled.

“You’re a soft one,” she said knowingly. “That’s good. This world could use more of those.”

Nurai didn’t even pretend to let them leave right away.

Katsuki tried. The second the last of the tiny spirits were settled, he stood, muttering something about “jobs to finish” and “not wasting daylight.” But Nurai only crossed her arms, raised a brow, and gave him a look so motherly and immovable that even he shut up mid-complaint.

So now, somehow, they were sitting cross-legged on thick floor cushions in what was clearly the living room, though calling it that felt too small for the space. The walls were lined with low shelves full of handmade toys, woven baskets, and tiny futons stacked neatly in the corner. A paper screen on one side was painted with rolling hills and fat, smiling clouds. The scent of tea and something freshly baked filled the air.

And Izuku had become a living jungle gym.

It started with one, some round, fuzzy ball of a yokai that rolled right into his lap and curled up there like it had known him forever. Then another floated down from a shelf and tucked itself under his arm. And then three more toddled or drifted over, drawn like moths to a warm flame.

Within minutes, he had a small crowd of baby yokai piled against him, napping, cuddling, occasionally letting out a chirp or squeak when he moved a little. One was sprawled across his thigh like it owned him. Another had taken residence on his shoulder and was nibbling his hair.

Izuku didn’t mind. At all.

“This is… Kind of the best thing ever,” he said quietly, stroking the soft, almost cloud-like body of the one in his lap.

Katsuki, sitting on the cushion beside him with his arms crossed, gave a grunt that could’ve meant anything from “You’re an idiot” to “I’m not admitting this is cute.”

Nurai came in with a tray of steaming tea and small cakes, setting it on the low table. She took one look at Izuku under his new blanket of baby spirits and chuckled. “Mmh. You’ve got the kind of energy they like.”

Izuku flushed, scratching the cheek of the little one snuggled under his chin. “I guess that’s… good?”

“It’s rare,” Nurai said simply. “Not everyone in this world has it. Hold on to it.”

Katsuki muttered something under his breath, but when Izuku glanced at him, there was no bite to his expression, just that same restless alertness he always had, like he was pretending not to enjoy himself.

Another baby yokai waddled over from across the room, bumping clumsily into Izuku’s leg before climbing up into his lap, squishing itself in between two others, like it was where it had always belonged.

Yeah. Izuku could definitely stay here for hours.