Chapter Text
FUBAR.
Shota Aizawa is not fond of using that particular acronym but right now it is extremely fitting for his current situation, as he sits inside Musutafu Police Station, filling out paperwork following the capture of a villain, all while stuck looking like his sixteen year old self. It could be worse. He wasn’t actually sent back in time, he still retains all of his memories and skills, plus according to the interrogation report, the quirk Shota was hit with has a time limit. One lunar cycle. It was a waning gibbous moon now, which meant he was stuck like this until the next full moon.
His best friends hadn’t stopped snapping endless amounts of photos of him from the moment they saw him at the station. Never mind that a villain had been trying to turn one of the students into a helpless baby before Eraser Head took the blow. A teenage Aizawa was apparently the best damn thing Yamada and Kayama had seen all year.
At least Midoriya was alright.
The boy looked so worried and guilt-ridden at Shota taking the hit meant for him. Even if Midoriya would have likely died had Shota not intervened when he did. So despite all of his grumbling and frustration at being stuck like this, Shota knows he’d do it all over again to keep his problem child safe.
“And with that last form, that should be everything we need Eraser Head. Thank you.” Detective Tsukauchi inclined his head in a slight bow of thanks before taking all of the paperwork from Shota. “Would you like a change of clothes to go home in?”
Shota looked down at his hero costume, now swimming on his smaller frame and exhaled in annoyance. How was he supposed to work like this?
“No, thank you.”
“If you’re sure.”
Shota bowed and shuffled his way out of the detective’s office to where Yamada was waiting with Midoriya.
“Sensei! I mean Eraser… I’m so-“
“Stop apologising, kid.” Shota glowered.
“You know, it doesn’t hit the same - you calling him kid when you’re back to being a kid yourself, Sho.” Yamada chuckled, very much enjoying how uncomfortable Shota was like this.
“Where’s Kayama?”
“Flirting with some officer. We came separately anyway so if you want to leave, I can drive us back to U.A. now that you’re too young to drive!” Yamada doubled over with laughter, slapping his knee with one hand as he fanned himself with the other.
“Just because I look young, doesn’t mean my actual age has changed.” Shota bit out.
“Try explaining that to the cop that pulls you over!” Then Yamada put on his best kid’s voice, “I promise officer, I’m a full fledged hero! Honest!”
“You could drive a motorcycle o-or motorised scooter… if you had one here…” Midoriya suggested, trying to make Shota feel better about the situation by finding loopholes in the law.
“The full moon is in just under a month. I can get by until then. Make yourself useful and drive us back to U.A. Yamada. I need to get changed out of these clothes.”
“Mind how you talk to your elders, kid. Put some more respect into how you address me.”
“Hizashi.” Shota growled.
“Fine! Fine! God, would it kill you to see how funny this is?” Yamada raised his hands in surrender and finally unlocked the car doors for them.
While Present Mic drove them back to U.A, Izuku Midoriya was having an internal crisis. Not only was he feeling extremely guilty for Aizawa taking a blow meant for him but now the teacher whom he had a secret, somewhat inappropriate crush on was now sixteen. Or at least had the appearance of his younger self. His mind was in meltdown. Aizawa had always been hot, in a dark, brooding, forbidden sort of way. But now, he was softer, his jaw wasn’t as defined and his scars were all gone. The dark circles under his eyes were not as pronounced. Even Aizawa’s hair was a little bit shorter.
How the hell was he supposed to act around his sensei now? He was still technically his teacher. Just because he looked young didn’t mean his mind had been altered. But no matter how Izuku tried to rationalise the situation, his body was reacting to the changes all on its own and it liked what it saw. It was a long and awkward drive back to U.A. while trying to hide the evidence of his attraction to a younger Aizawa. He was very tempted to use his quirk the moment the car stopped to rush to his dorm room and finally take care of his growing problem.
Those plans were thwarted as Principal Nezu was waiting for them before they even parked. He was smiling but the agitated swish of the chimera’s tail suggested that he was more worried than he let on. Was he angry that one of his favourite teachers had been harmed because of a student? Would Aizawa be in trouble or not be allowed to work because of this? Was he going to-
A small hand on top of his startled Izuku out of his tornado of thoughts. Izuku’s eyes widened in shock as he realised that small hand belonged to Aizawa.
“Stop worrying, kid. The rat’s not mad. Just worried for your safety.” It was strange hearing Aizawa speak to him in a higher register than he was used to. He kind of missed the deep rumbling way Aizawa spoke but teenage Aizawa sounded a little… kinder? More gentle, maybe. Izuku just nodded and followed his teachers out of the car and up the steps to the Principal.
“My, my, Aizawa-kun. The anti-ageing cream you use worked a little too well.” Nezu joked, earning a deafening laugh from Present Mic.
“Very funny.” Aizawa said coolly.
“I must confess, I spent the last thirty minutes coming up with it!” The chimera beamed at them, “It is good to see you unharmed, young Midoriya. You had several of us quite concerned when Detective Tsukauchi called.”
By ‘several of us’, Nezu meant All Might. Hopefully his mentor wasn’t too upset with him.
“If the detective already called you, then you know the villain was targeting Midoriya specifically.” Aizawa said with all the same authority he did as a grown man. It still sounded strange coming out of a teenager though.
“Indeed. Most worrying. There is enough pressure on our students with the threat of the League. We didn’t need to add more. It is a good thing they’re in custody now,” Nezu rubbed his chin thoughtfully, “I shall let you go rest, Aizawa. We can discuss what happened tomorrow.”
“Yo, do you even have clothes that’ll fit you now?” Present Mic asked, finally serious.
“I’ll figure something out.” Aizawa grumbled.
“You c-could borrow some of mine!” Izuku said the words without even thinking, just wanting to help his crush teacher anyway he could. This was his fault, after all.
“Huh?” Aizawa looked at him with a puzzled expression.
“I… I doubt what clothes you have will fit you any better than your hero costume right now… so borrow some of my clothes. You know, until the quirk lifts. This isn’t permanent so there’s no point in buying new clothes, right?” A logical argument almost always worked on Aizawa-sensei. Izuku could see him mulling over his options until he reluctantly came to the same conclusion.
“Fine. Show me what you have.”
As they approached the class 1-A dorms, Izuku realised no one in his class knew what had happened and they were all in there, eating dinner right now!
“Umm… maybe we should go in the back way?” Izuku blocked Aizawa’s path in a panic.
“Why should we? The door is right there.”
“Because everyone is inside… having dinner… We won’t be able to sneak past them.”
“They’ll find out about it sooner or later.” Aizawa shrugged, trying to side-step around him but Izuku moved with him.
“True, but wouldn’t you prefer to be wearing clothes that fit?” Izuku countered.
Aizawa frowned at Izuku, then looked down at himself before sighing in defeat and heading for the back stairwell instead.
“Of all the things I thought I’d be doing tonight, sneaking into the dorms with one of my students was not one of them.” Shota mumbled under his breath as he quietly unlocked the back door. His sensei hadn’t meant it to sound salacious but Izuku couldn’t help but hear it that way. Biting the inside of his cheek, Izuku willed his body to calm back down. He could not be sporting a boner when Aizawa was going into his bedroom.
“What were you hoping to do tonight?” Izuku whispered, trying to redirect his thoughts to safer ground.
“Something thrilling like grading papers or putting together lesson plans for next week.” Aizawa replied sarcastically.
“You don’t go out and have fun?”
“How much free time do you think I have between teaching you lot, hero work and taking care of Eri?”
“Good point.” Izuku quietly opened his bedroom door and gestured for Aizawa to go in first, “But if you could-”
“Argghhh… So much All Might…” Aizawa cringed at the wall to wall display of hero merch everywhere.
“It’s not just All Might!” Izuku got defensive, “There’s Present Mic and Midnight. Oh and Mirko and Hawks and Edgeshot… See? I even have a custom made Eraser Head mochi plushie.”
“You made this?” Aizawa asked incredulously.
“No. I’m not great at sewing. But I designed it and had someone else make it! There are websites that do that.”
“Why would you waste your money making something in my likeness?”
“Its not a waste!” Izuku got indignant, “Besides, there’s no official merchandise of you. I wanted something… f-for all of my U.A. teachers…”
It was more than that but Izuku wasn’t going to admit it.
“Let’s see your clothes then.” Aizawa changed the subject and they began sorting through Izuku’s clothing, holding some shirts up to his chest to gauge what would fit.
“Huh… I just noticed… I’m actually slightly taller than you now.” Izuku stood almost nose to nose and held his hand up to compare heights. “Yep. By a few centimetres.”
“Give it a few weeks and I’ll have a hell of a growth spurt.” Aizawa said dryly, his cheeks looking a little redder for some reason before the man stepped away to pull his hero costume off.
Izuku had gotten changed in front of his classmates hundreds of times and never once been bothered by it or even excited at being surrounded by other naked men. But Aizawa stripping down to his underwear in Izuku’s own bedroom had the green haired boy going dizzy for a moment. He disguised it by plopping down on his desk chair, trying to look bored as Aizawa tried on a few of Izuku’s clothes. They looked a little baggy on him but not as bad as the hero costume had. At least the waistband on the pants fit fine so he wouldn’t have to worry about it slipping down while he walked.
“Why do all your t-shirts have contrary words on them, like ‘dress’ or ‘suit’?” Aizawa asked.
“Because it’s funny!”
“You have a terrible sense of humour.”
“You don’t have to wear them if you don’t like them.”
“It’s either those or All Might merch. I can stomach the bad jokes better than being a walking billboard for him.” Aizawa gathered a few t-shirts, hoodies and pants in his arms and headed for the door. “Thanks for the clothes. I’ll be sure to wash them before returning them to you.”
“Wait! Do you need… umm… underwear?” Izuku whispered the last words, blushing from embarrassment.
“No need.”
With that, he left. Izuku sat there, trying to figure out if ‘no need’ meant that Aizawa had underwear that would fit or if he didn’t wear it in the first place. His little problem from before returned with a vengeance. At least now Izuku could lock his door and take care of it.
Wearing Midoriya’s clothing was strange. At least the kid was clean and looked after his stuff but the boys taste in apparel was appalling. Well, Shota only had to stick it out for a month then he could return the terribly unfunny t-shirts. Maybe as a thank you, he could buy the kid some better clothes. Ones without All Might or katakana plastered all over them. Dressed and ready to brave the gawking and heckles he was bound to get from the other teachers, Shota went downstairs to finally eat dinner. Yamada was waiting for him in the kitchen, a plate of curry in one hand and a cup of coffee in the other. The perfect combination.
“Made it just how you like it.”
“Thanks old man.”
“HAHA! Finally giving some back huh? Come on! Everyone’s dying to see you like this.” It was unsettling how much Yamada towered over him now. At least his hair was pulled back into a low bun and not sky high like a cockatoo.
“I’m stuck like this for nearly a whole month. They’ll see it eventually.” Shota grumbled.
“Just rip the bandaid off, mate.”
With a long-suffering sigh, Shota trudged into the dining room with Yamada. The room went silent for a moment as people stopped talking and eating to stare at their work colleague looking more like one of their students.
“Interesting choice of clothes, Eraser.” Vlad was the first to speak up.
“They belong to Midoriya.” He tried to sound threatening, but his vocal chords had other ideas, voice breaking mid-sentence to really drive home that he was a teenager again.
“Oh my god, your voice broke! That’s so cute, Shota! Do it again!” Kayama cooed from her seat.
Rather than speak and subject himself to further humiliation, Shota just flared his quirk at her before sitting down to eat. A few bites into his curry he realised it was way too spicy for him, which was odd. Shota liked a bit of heat but this was too much. Has someone made this super strength spicy? It didn’t look bright red like the hottest sauces usually did. In need of something to put the fire out on his tongue, Shota sculled his coffee, downing a third of it before he nearly spat that out too.
“Blehhhh! What the hell did you do to my coffee, Yamada?” Shota complained. So much for making it how I like it!
“Nothing! It’s a little stronger than I like it but you’ve been drinking your coffee black for years now!” Yamada said defensively.
“Then why does it taste wrong?” Shota snipped.
“How did you take your coffee when you were younger, Aizawa?” Thirteen asked tentatively.
“Huh?”
“Ohhhh! You think his taste buds have reverted too?” Kayama caught on quickly, “Maybe add some milk and sugar. See if that helps!”
Just great. Not only am I stuck back in this younger body but my tastes have gone back to what they were back when I was in high school too? This is going to be the longest month of my whole damn life.
Refusing to accept that his body couldn’t take drinking strong black coffee anymore, Shota stubbornly forced himself to drink the rest, even if it did taste god-awful. Like hell was he going to add sugar to anything!
The next morning, Izuku was a nervous wreck for homeroom. No one else knew the truth about what happened with Aizawa-sensei. He had wanted to tell them over breakfast but he honestly didn’t know if he had permission to talk about the patrol yet. When their teacher was uncharacteristically late, his classmates began speculating what the hold up was. Finally, Principal Nezu walked in, hopping up on Aizawa’s desk and clearing his throat to get everyone’s attention.
“Good morning, students!”
“Good morning, Sir!” Ida responded boisterously on behalf of class 1-A.
“You may or may not be aware that your homeroom teacher, Aizawa-kun, was caught up in a targeted villain attack last night.”
“Oh no!” “Is he okay?” “Someone is targeting Sensei?” “What happened?” “Is he in hospital?” “Are you teaching us today, Sir?” “Wasn’t Deku on that patrol too?”
“He’s is alright, although not quite himself. Why not just show them, Eraser? Then we can answer their questions.” Nezu called out to the corridor and waited for Aizawa to shuffle inside, wearing a U.A. sports uniform with his signature scarf on his shoulders.
The comparisons to Shinso are only going to get worse after this.
Shocked silence settled over the classroom before a cacophony of squeals and laughter burst forth. Izuku was sure the classes down the hall could hear them. It took a couple of minutes for everyone to calm down enough before Nezu would answer any of their questions.
“What happened exactly?” Uraraka asked first, puzzled at how their homeroom teacher was their age now.
“A villain with a body-altering quirk managed to hit Eraser last night. Thankfully it is not permanent. He will be like this until the next full moon.” Nezu explained and Izuku noticed that he had conveniently left out why Aizawa got hit.
This is all my fault.
“Is his quirk okay?” Kirishima asked.
In response, Aizawa activated his quirk, red eye flashing and dark hair floating upwards. It wasn’t as intimidating as a fully-grown Aizawa yet it still sent a thrill down Izuku’s spine.
“So Aizawa-sensei, your mind is still that of your older self?” Yaoyorozu double-checked, looking uncertain about the whole situation.
“Yes. For whatever reason, the quirk doesn’t affect brain functionality. I can still teach you brats like normal, no matter what I look like.”
“Indeed. While it may be rather unusual to see your homeroom teacher like this, please remember he is still your Sensei, students, and should be respected as such. I shall leave the class to you, Aizawa. Happy learning, everyone!” Nezu waved enthusiastically as he left the classroom. Aizawa-sensei was quick to use his scarf to slide the door shut behind him.
“I hope you brats are ready for some drills today.”
Even as a teenager, Aizawa’s sadistic grin was terrifying.