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Izuku could barely hold in the bundle of excitement that he felt when he heard the assignment. A full day disguise assignment. They had to make a disguise and wear it, while acting in character, for an entire day. They could be anyone, real or fake, but they had to have a solid background understanding, and if it was real, they had to act like the person, although the voices could change.
It was pretty much Izuku’s dream assignment. Especially when Aizawa said that if anyone impressed him enough, they would get to join him for a small undercover mission he was going on a week afterwards. Izuku was desperate to see how that kind of operation would go, partially because he adored the idea of underground heroics but knew that wasn’t an option for him. He had to win.
Luckily, Izuku had one thing no one else did. Over a decade of cosplay experience. He knew for a fact he could perfectly replicate someone, he just had to work out who and if he could change his voice… well there would be no way for Aizawa to reject him then!
Aizawa gave them some time to plan, and Izuku carefully made sure he kept his mouth closed, avoiding his natural mutter. He was going to destroy everyone and to do that, he had to keep it a huge secret.
So, who should Izuku choose? It had to be someone he knew well who he could play off, although that left all his classmates and most pros. If he wanted to use some sort of software to speak for him, he would want someone monotone, someone who didn’t particularly change their voice as they spoke. Todoroki was an option, but if Izuku showed up as Todoroki, it would be obvious it wasn’t him, since Todoroki would be in disguise. No, he needed someone else.
Izuku’s roaming eyes landed on his target.
Aizawa did not see it coming.
——————
The week they were given to prepare had most students running around frantically, trying to create a fake identity, but Izuku already had a perfect Eraserhead costume- sleeping bag and all, so he only had two goals. 1) he needed to work out how to grow 17 centimetres, and 2) he needed to get enough recordings of Aizawa’s voice to go without suspicion.
The first one turned out to be the harder one (the soundboard app on his phone working perfectly for the other job) but by the end of the week, Izuku had managed to redesign his Eraserhead boots so he could comfortably stand (and walk) on the top of the boots rather then where the foot would normally go. It felt a bit scuffed, but looked perfect regardless.
Izuku was insanely glad he had already designed the human hair wig with the same hair type as Aizawa (his highest quality wig from his stash) to not only be exactly the right haircut and style, but also have wires carefully threaded through it to allow a single button press to raise the hair. That combined with the insanely expensive eye contacts that could change from black to red upon double blinking, should be enough to thoroughly convince everyone that he was Aizawa- provided he only used his ‘quirk’ on people who weren’t actively using their’s. Which, if they were trying at all on this assignment, would be all of them.
——————
On the day of the assignment, Izuku didn’t make an appearance in the common room before school but he doubted anyone would be suspicious- probably helped by the fact that he had told the class he was going to go as Hagakure. He didn’t doubt they thought he was just going to hide somewhere and talk… maybe he would do that too, just to mess with them. Either way, he took advantage of the extra time (and the hour earlier he had woken up) to perfect the makeup, grinning at how perfect the scar was- genuinely some of his best work.
He walked into class exactly two minutes early with all the tiredness that Aizawa exuded, holding a replica of the teacher’s favourite mug filled with the exact same brand of coffee he always used. He unceremoniously left the cup on the desk and clicked on the first of the soundboards, carefully lip synching to it.
“Home room is a study session today. Keep the noise down. I’m having a nap,” and with that, Izuku expertly crawled into his sleeping bag and sat in the exact spot Aizawa always did, keeping his eyes just barely open in the way he knew his teacher did, observing the class. The small details were key. Izuku had even made a plan if Aizawa had already been in class, with a multitude of “who are you!?” And “it’s toga! Get back!” And “raise the alarm!”, but none were necessary. Yet.
He looked around at the class, finding Hagakure had decided to go as 13, a wise choice since her invisibility didn’t exactly help the assignment, so full covering would be her best bet.
Tsu and Uraraka had surprisingly elegantly swapped, pretending to be each other, and honestly they did it well enough that he might have hesitated on who they were if they hadn’t stupidly gone to their own seats.
Tokoyami was Hawks, and he kept explaining that his head was different because he had been hit by a weird quirk on patrol the previous day. He had pretty much perfected Hawks nonchalance, and the fact that those were definitely Hawks’ actual wings (the feathers were floating around and actively helping Tokoyami’s disguise while also poking him annoyingly) was definitely a good detail.
Iida had clearly just borrowed his brother’s costume, which in Izuku’s opinion was kind of lame and disappointing for the boy who usually put a lot of effort into assignments. He wasn’t even doing a remotely good job at pretending to be his brother, who had a wildly different personality.
Momo had cleverly come as a tourist, and was only speaking in Mandarin. She also had her hair down- something Izuku was only now realising he’d never actually seen before- and had added a bright blue hair extension. She had also pretty effectively contoured her face to change its appearance.
Kachaan was hunched over Izuku’s desk with green and black hairspray mixed into his hair which he’d clearly curled. Kachaan was also pretty effectively matching Izuku’s normal mutterings in a reasonable approximation of his voice.
Izuku was still caught trying to work out of Kachaan was mocking him or just actually trying because he knew Izuku the best when the door swung open and revealed Mic Sensei- no, Aizawa Sensei in his husband’s costume. Izuku grimaced internally because despite the fact that he was pretty sure no one else other then Shinsou knew the two were married, the class did all know how they interacted. Something with Izuku was going to have to imitate. Great. (Izuku was not keen on that)
“Hello Listeners!” Mic Sensei’s voice boomed, and it took Izuku a moment before he found the support item on Aizawa’s neck that was likely changing his voice. He watched silently as the underground pro made eye contact with him, flashed his quirk (clearly checking it wasn’t Toga), before scanning the class and returning his gaze to Izuku with a smirk.
“Mic,” Izuku greeted with a tap on his phone. Giving Aizawa a look that silently asked the question of ‘will you play along?’
“Shou! I’m so glad I could join your class today! Disguises are epic!” Aizawa grinned wildly- Izuku wasn’t aware the pro knew how to smile like that- but either way it was a clear answer that yes, they were doing this.
Izuku swiftly set up an order of the words, suddenly grateful that he could hide his phone in his sleeping bag.
“They have a study session. Feel free to interrogate them all.”
“Will do!” Aizawa boomed, swiftly moving off without the lovesick expression Mic always sent Aizawa’s way before leaving. Izuku was immensely grateful Aizawa hadn’t don’t that.
He listened as the teacher made his way around the class, picking apart their disguises and asking questions upon questions about their identities.
Momo clearly hadn’t anticipated anyone knowing Mandarin, and from the bits and pieces Izuku could make out, she was not a good liar. A good choice if you can’t lie, but not if they speak the language.
Kirishima’s Red Riot cosplay was very high quality, and his fan knowledge was undeniably firm, but when it came to more personal questions, Kirishima didn’t have much choice other then to say ‘that’s private information’. It worked, but it could have been better. Also, he could work on his makeup too, but it was a reasonable attempt.
Mina’s had to be one of the best attempts. She had created a fake backstory, all the way down to a different quirk that she could fake- a mild fire based quirk that burnt her handprints into stuff, which she just used a highly corrosive acid for. She’d also covered every single bit of bare skin in foundation and straightened her hair into a bob- something Izuku personally did NOT like, because it was weird for his curly hair buddy to have straight hair. She’d also hidden her horns under a beanie. Overall it was extremely good, and Izuku couldn’t help but be proud.
Aoyama had gone for a similar route to Momo, but had put in a lot less effort, and had struggled over the fact that he clearly had no planned story to fall back on.
Ojiro and Sero had both rather skilfully hidden their mutation quirks in ways that Izuku was a little concerned over. Mutation quirks tended to be discriminated against, and those weren’t easy to conceal, so the fact that it was concealed so thoroughly was worrying.
Izuku let himself analyse every member in the room, subtly typing notes on his phone for how they could improve, because they all could improve. Occasionally he would throw his normal voice across the room (a skill he was quite proud of) and watched as everyone tried to work out where he was hiding. The first time he’d done it even Aizawa had seemed confused, before his eyes landed on Izuku’s perfect replication of Aizawa’s ‘logical ruse’ smirk.
When the class finally left for lunch, Izuku didn’t move, carefully holding up his facade. He had an assignment to win and he would win it.
“You can drop the act Izuku,” Aizawa’s own voice this time spoke. Izuku however, just raised his eyebrows, flashing his eyes red for a second to give him time to construct a sentence.
“I don’t particularly like what you are implying ‘Zashi,” Izuku responded, carefully holding back the giddy grin at the way Aizawa’s face contorted in surprise for a moment at the nickname Izuku definitely was not supposed to know.
“What is this? Why did you call me that?”
“Students aren’t around,” Izuku replied evenly through his sound board.
“Right, and who are you to me?”
“Did you get hit by a quirk? You’re my husband,” Izuku had to do his best genuine recreation of Aizawa’s voice for the last word which he hasn’t managed to make a soundboard for. Luckily, Izuku had also been training his voice to mimic his teacher’s gruff tone.
“Alright how do you know that hellion?”
“That’s my word,” Izuku complained in Aizawa’s voice.
“I coined it. You are just pretending to be me.”
“Not sure what you mean.”
“Izuku, you can’t gaslight me into thinking you are me, no matter how good your disguise is.”
“I can try,” Izuku grunted in his Aizawa impression, stepping out of the sleeping bag.
“You really can’t.”
“I am Aizawa Shouta, also known as Eraserhead. I’m married to Yamada Hizashi, also known as Present Mic and have an adopted daughter called Eri, along with three cats, and my foster son Shinsou Hitoshi. My quirk is erasure, what else do you want me to prove?” Izuku asked, flaring his ‘quirk’ at the last line with a glare.
“How the fuck did you do that?”
“That’s my quirk. Did someone hit you in the head?”
“That’s my quirk problem child,” Aizawa responded, sending his own red eyed glare Izuku’s way.
“That didn’t do anything to my quirk. You are just some copycat. What can I do to prove I am who I say I am?”
“What’s my- Aizawa’s- birthday?”
“November 8th, but I tell my students it’s December 23rd because they won’t be at school at that point to annoy me about it.”
“Where were you born?”
“Tokyo, is this really relevant?”
“Who was the first casualty on your watch?”
“Oboro. Even if you say it wasn’t my fault, I can’t help blaming myself.”
“What. The. Fuck?”
“Sorry.”
“Is there anything in my life you don’t know?”
Izuku hesitated, unsure if he should break character.
“I’m giving you a 100% on this assignment, you tricked the entire class so fully that no one noticed the flaws in my own disguise. You grew 6 inches, and you have my voice- although it was better earlier, it’s still on point. You made yourself sound like you were somewhere else, eliminating suspicion, and you even have my quirk and my face. Yeah, I’d say that’s worth 100%.”
“And the mission?” Izuku asked, still in Aizawa’s voice.
“And the mission,” Aizawa sighed. Izuku grinned, real and true, “That looks weird on my face.”
“Do you like it Sensei? The contacts were expensive as hell, and when I first ordered them it took months to arrive, so that would have sucked if I didn’t already have them. And the hair too! This wig took me 37 hours to style and set up, it took years off my life, I swear. And the scarf! I’m so proud of it and I didn’t even get to show it off, look!” Izuku flung the scarf out and gripped Iida’s water-bottle with it, bringing it back to his hands, “Fully functioning and everything! Oh and I don’t know where you managed to buy that sleeping bag, because I had to make mine from scrap, even just getting fabric that colour is hard! And the boots! I’m so proud of that one! The height was genius and-”
“Woah, ok, slow down, this is already a lot to take in. First you know a disturbing amount of things about me- including things I purposefully hide because it’s dangerous for people to know- and now you are breaking down how you made this disguise and I need just a moment to process, that’s all.”
“Oh, I can help with that, I’m a cosplayer, I already had most of it done before you announced the project so then I just had to work on fine tuning the height and getting your voice, I used a soundboard, and some of my best imitations for that.”
“And the things you know that you definitely shouldn’t?”
“Oh, mostly I’m just really observant and people don’t tend to notice when I’m around. You are more aware then most but you still miss me a lot, I’ve been told I move very quietly, it’s not intentional, I swear!”
“Do you worked out all of that from unintentional eavesdropping?”
“That and some other observations. Your ring tan line, you don’t wear your ring when you’re in gear, but you mostly work at night so that fact hasn’t quite undone the tan line yet,” Izuku explained, holding out his own hand to point to the light tan line he’d faked, “Plus anyone who is really paying attention can see that Mic-Sensei gets away with far more then anyone else does, and I’ve walked in on Midnight-Sensei sometimes teasing you two in the staff room so those kind of just connected. Eri and Shinsou are too close for the amount they see each other for there not to be a relationship there, and when I asked Eri, she told me he was her brother. She faithfully didn’t mention you two, but she said it was a secret which just added to my knowledge and-”
“Alright, I’m going to stop you there before I have an existential crisis over how lax my secret keeping skills have gotten.”
“If it helps, I don’t think any one else knows about it? I’m kind of an exception…”
“Why is that?”
“Well I’m actually a huge fan, you’re one of the heroes I knew I could trust growing up and basically I just locked onto you. Especially after… after the sludge incident, you became my favourite hero.”
“The sludge incident?”
“Oh, nothing important, anyway, you were my favourite hero and I cosplay lots of heroes, but yours is by far my best cosplay!”
“Yeah, yeah I’d say it is.”
“Yeah, so anyway I’m a big fan so I know a lot more then most do.”
“Alright, I’ll grant you that, but why are you so quiet that even I- a trained pro who specialises in surveillance and underground heroics- didn’t notice you?”
“Practise?” Izuku offered weakly.
“Why?” Aizawa asked- no, demanded. There was no avoiding this question.
“I kind of got bullied a lot? So I just learnt how to stay out of people’s way?”
“Why did they bully you?” Aizawa asked, his voice softer, less harsh, but no less insistent.
“I’m quirkless- or well I was obviously not anymore, but yeah. Quirkless. Got me a lot of skills”
“Have you ever considered underground heroics?” Aizawa asked, carefully soft.
“All Might wouldn’t like that,” Izuku admitted, covering his mouth with his hand. He hadn’t meant to say that.
“Why the fuck would that matter?” Aizawa asked, angry, but not at him? Izuku didn’t think it was at him.
“I kind of have All Might’s quirk and I’m supposed to be the next Symbol of Peace so I guess I’m going to be a limelight hero because it’s his quirk I have to follow what he wants.”
Aizawa have Izuku the look he always had when he was getting a headache. Izuku winced and pushed the coffee he had made this morning towards the hero. He had a feeling this would be a long lunch.