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Katsuki didn’t have any control of his quirk. He wasn’t creating explosions anymore. He was exploding. He no longer had a body of his own. His mind and his heart and the gravitational pull of his entire being–they were all pointed in one direction: All For One.
Izuku was dead. His Izuku was gone. He watched Izuku crumble. He watched Izuku’s body smack against the ground and not move. He was too far away to hear the thundering crack against the ground but he felt it cleave his soul in two all the same.
But Izuku couldn’t be gone. No, Katsuki couldn’t do this without him. Not just the battle or being a hero. How was he supposed to exist without Izuku in this world too? He couldn’t. It wasn’t possible. Everything would be out of balance, out of order, all wrong.
The explosion that he was inside of was moving. Moving towards the horrifying mass of power that was All For One. He knew he wouldn’t win. There was no winning without Izuku. That didn’t matter now, though.
Kirishima screaming his name didn’t matter. Aizawa’s shouts to stop didn’t either. Not even the thought of his parents waiting at home could stop this now. It wasn’t about choice. He didn’t decide to ignore all of their pain. He just couldn’t stop. He was exploding. He was coming apart at the seams. It started the moment he saw Izuku’s body stop moving. The moment he realized Izuku wasn’t getting up, he knew one thing: he wouldn’t survive either.
But maybe if he detonated close enough to All For One, it could put a dent in the villain’s defenses. Maybe the other heroes could finish the job for them. Either way, wherever Katsuki ended up after death, he was going to find Izuku. His Izuku.
All For One’s eyes went wide as Katsuki burst apart in front of him. Maybe he knew what was coming. Maybe he realized too that Katsuki didn’t intend to survive this final blow. Maybe he realized that this sacrifice was exactly what the heroes would need to get rid of him for good.
He didn’t feel any pain at the end of it. No, it was all over too quickly for that. He saw white, blinding light. Then… nothing. He saw nothing and he was nothing. He floated in that black abyss for only a second but simultaneously a thousand years. There was no space or time there. How could there be?
But then he saw a light in the darkness. Not a glowing white thing. It didn’t have soft edges or a defined shape. It was a spark, bouncing around erratically. A flash of lightning. It was green and beautiful and looked like home.
Suddenly he wasn’t floating in nothing. He was sinking in black water. It was cold like rain. He kicked and scrambled and fought to move toward that light. He had to get to it. He knew what he would find there. He knew who he would find.
Izuku, he silently called out, the only real thought on his mind. Izuku!
He breached the surface but waves didn’t crash down on him. No, he could stand up now. Shallow water flowed around his ankles gently like a creek. He saw the spark again, bouncing around like a too-quick rabbit. He reached for it, tried to catch it. His hands never managed to clasp around it. It was too fast.
“Izuku,” he pleaded, begging. “Izuku.”
The spark stopped moving, halting just outside of arms’ reach as if it was hesitating for a moment. It vibrated and sparked in the air in front of him.
“Izuku,” he said again, calling out to it. He reached his hand out slowly. If he could just touch it. If he could just see Izuku for another second, he would take it. He didn’t have to capture the spark. He didn’t need to own it or leash it. Maybe he could just sit and watch it. “Izuku.”
The spark fizzled and popped, expanding like a freshly lit sparkler. It was beautiful. Katsuki held his palms up, unafraid of getting burned. He stopped fearing that a long time ago. The mass of sparks slowly moved closer to his palms, as if lowering itself down to him. He didn’t move, not wanting those sparks to run away again. He didn’t know how he knew that this was Izuku, or part of him. But he did.
As he felt the first tiny sting of those sparks, he was ripped away.
He shot up in bed, clutching at his pounding heart and breathing too quickly to actually get any air. His body started moving without thought, fighting against the sheets and blanket around him.
He fell hard against the ground and it somehow locked air into him. He gasped and drew in a rough breath, the kind that tore apart a person’s throat. He continued drawing in breath until his lungs weren’t burning with need. His chest was still squeezed tightly and painfully, as if his heart were trying to implode still. It left him close to paralyzed, staring down at the floor inches from his face. Then he saw his hands, palms flat on the cold wooden floorboards. They looked wrong–too small, too clean.
He scrambled into a sitting position, eyes moving up to his arms. They were less defined and there wasn’t a single scar on them. He didn’t know how he managed to put his legs under him and stand. He didn’t feel strong enough to walk and yet he ran.
As he looked into the full-length mirror in his bedroom at his parents’ house, he flinched back. He fell to the ground hard enough to probably bruise his tailbone. Still, he stared at his reflection. The red eyes, unyielding spiky blonde hair, and general features were all familiar. But he hadn’t looked so small, so slim and clean for a while now. He recognized this version of himself from all the photos his parents still insisted on keeping hung on the walls.
This was his middle school body.
He twisted around, spotting his phone on the nightstand. He reached for it without bothering to get up from the ground. As soon as he clicked it awake, the screen lit up to show an old wallpaper: a still shot from an epic All Might battle in his Bronze Age. All Might was hiding his fist up in victory and smiling wide. Katsuki remembered changing that wallpaper from All Might after getting into UA. He felt too embarrassed of the idea of All Might himself seeing it.
His eyes shifted to the time and date displayed near the top of the screen. He didn’t gasp. No, he felt frozen by shock. Was this a dream? Was this what heaven was supposed to be? A second chance at everything?
Most of the regrets in his life came from this age. Middle School Katsuki couldn’t accept Izuku in his life–he was too scared of the hero Izuku Midoriya always was–the hero he was born to be, while Katsuki always felt two steps behind. He’s tried to cover it up with arrogance and explosive anger. He couldn’t accept that Izuku was a better hero–a better person–than him even without a quirk. He lied to everyone, including himself, pretending that he was better and that Izuku was scum. He was horrible to Izuku, bullying him as if that could change their fate.
According to his phone, he wouldn’t have school today. It was also early morning, just after the sun would have risen. He looked at the window, seeing dim light seep into his old room. He couldn’t wait until tomorrow to see Izuku. He didn’t know how this all worked–if he was supposed to pretend everything was normal or if this was temporary or if he should go along with the correct timeline he remembered. He didn’t care if he was honest.
All he cared about right now was seeing Izuku. Alive and smiling and before he was ever hurt. Before scars covered his body. Before the darkness of All For One began haunting them. He needed to find Izuku.
Would he remember the future like Katsuki? Would he remember his death or their battles?
Katsuki changed into jeans and a familiar-looking skull shirt. It pained him to take the time to do so but he didn’t know how he would explain things to his parents if they saw him wearing pajamas and running out of the house. He didn’t want anybody stopping him.
Minutes later, he shoved the phone into his pocket and ran down the stairs. His father was there in the kitchen, smiling warmly at him. His mom was drinking coffee and leaning on the counter beside him. Her mouth opened, loudly chastising him for the ruckus he was making upstairs.
“I have to go see Izuku,” he said, interrupting her mid-sentence.
Both of his parents froze, staring at him as if he were from another planet. He didn’t know if it was because of his destination or the fact that he hadn’t yelled back at her. It didn’t matter. He could deal with their confusion later.
He used their shock to slip out of the door without argument and began running. He didn’t live far from Izuku, only a few minutes away really. He didn’t have the patience to walk or bother with politeness as he shoved past other people on the sidewalk. He just needed to get to Izuku.
When he stood in front of the Midoriyas’ apartment door, he was huffing. His heart was beating a million miles an hour. His lungs burned and his entire body was coated in pins and needles. Numbly, he raised a fist to the door and knocked.
Thunk, thunk, thunk.
It took a moment for anybody to open the door. He wondered if this Izuku would even answer when he saw it was Katsuki outside. He wouldn’t blame Izuku for that. He should hate Katsuki for everything that he had done, everything that he had said.
But of course he didn’t.
Izuku opened the door wide, brows pinching together a moment later with confusion. “Kacchan?”
Hearing that name, hearing that voice, seeing those wild green curls and those freckles–maybe this really was heaven. Katsuki stood frozen, unsure what to do now that he had Izuku in front of him. The green-haired boy didn’t seem to understand what he was doing there so he must not remember anything. It was just Katsuki that was thrust back into the past then.
Izuku looked tiny. How did he not remember how tiny Izuku was back then? Katsuki was always taller and bigger than the other boy but this Izuku was slim and reserved in a way that made him appear even smaller. Katsuki had done that to him. It was Katsuki’s fault.
“Kacchan?” Izuku said again, green eyes wide. He sounded worried. Why was he worried? He probably thought Katsuki was there to hurt him.
It made him flinch back. He didn’t want to scare Izuku anymore. He just wanted him. He wanted to–he needed to say something. He needed Izuku to know that it was Katsuki’s fault. He needed to know that Katsuki wouldn’t ever hurt him again. He needed to know that Katsuki would stand with him, like they promised when they were little: partners until the end.
Izuku stepped forward, out of his apartment. A slim, unscarred and freckled hand reached up as if to touch Katsuki’s face. A second later, his fingers curled in, the hand being pulled back. No! No, no, no, it was okay. Izuku could do whatever he wanted. He would do anything to make it all up to Izuku.
His legs failed him. Down on his knees, he stared up at Izuku. Somehow this made Izuku panic even more. “Kacchan! Kacchan, are you okay? What happened? Are you hurt? Why are you crying? Kacchan?”
Izuku was speaking a thousand words a minute but Katsuki became fluent in that long ago. Wait, did Izuku say he was crying? His own hand reached up to his face, feeling the wetness on his cheek. He looked at the moisture stuck to his fingertips then back up to Izuku.
“I’m sorry,” he said, unable to think of any other words. “I’m sorry for everything. I hurt you and pushed you away because you were strong even without a quirk. I had one but I was always inferior to you. I’m sorry, Izuku. I mean it. Please, Izuku, I’m so sorry.”
He knew he was crying now. This version of himself wouldn’t have dared show such weakness, especially to Izuku. But he wasn’t the same person anymore. He knew now how wrong he had been. Izuku was a hero–he always was. He was Katsuki’s hero. Everything he strived to be and compete with and win beside. He was everything.
Izuku was silent for a moment before tears began streaming down from those big green eyes. No, no, no, no, that wasn’t supposed to happen. He was trying not to hurt Izuku anymore. He was trying to make things right this time–
Izuku’s arms wrapped around him as he fell down to his knees in front of Katsuki. His hold was strong despite the skinniness of those arms. Katsuki couldn’t help himself. He hated people hanging all over him, even his parents, but Izuku was an exception. Izuku was always different from everybody else. His own arms came around Izuku, clinging like some kind of baby. His fingers curled in the back of Izuku’s shirt, clenching hard enough to hurt. Izuku pulled him close, their faces tucked against each other’s shoulders.
“Kacchan,” Izuku cried into his neck, holding tighter somehow. “It’s okay. Don’t cry. Don’t cry, Kacchan. It’s gonna be okay.”
Izuku wasn’t supposed to be comforting him. He should hate Katsuki. But of course he didn’t. He never did. He never hated Katsuki and never looked down on him. Izuku was too good for that.
“Izuku, I promise I’ll be better,” he said. “I promise I’ll work to deserve your forgiveness.”
Izuku only cried harder. “You don’t have to, Kacchan. You already have it.”
Katsuki wrapped his arms further around him as if he could fuse them together. “We’ll do it together. Everything. I’m so sorry it took me so long to remember our promise, Izu.”
We’re gonna be hero partners one day. I promise.
“That’s all I ever wanted,” Izuku said, muffled by Katsuki’s shirt.
Katsuki didn’t want to be so far from Izuku but he pulled back, his hand coming up to frame the freckled face in front of him. Tears still spilled from Izuku’s eyes but he looked so beautiful. He really was amazing. He was better than Katsuki could ever be. But Katsuki would work to be worthy of the boy in his hands.
“I promise,” he whispered again.
Izuku’s hands in his shirt tugged, pulling him closer until their foreheads were pressed together. “I believe you, Kacchan.”
Katsuki didn’t deserve a second chance like this. He didn’t deserve this reincarnation or whatever it was. But he would do everything possible to get things right this time. He would help Izuku train before they met All Might and he would make sure All Might still picked Izuku as the successor for One For All and he would make sure that Izuku was ready this time. They would win this time. They would win and after it was all done, he’d keep their promise. They would be hero partners. Together until the end.