The silence in the empty classroom was rather jarring for Izuku.
He'd never been in such close proximity with Katsuki without something exploding or the blonde yelling his head off, and now that his friends had all left to go home, he was left completely without the buffer of being in a group, which did not bode well for his confidence.
It annoyed him to think that despite all he'd been through he was still the scared little kid he had always been, well except for the fact that he got annoyed at people a lot faster than before, which wasn't exactly completely his own fault, it was a mixture between not having much social interactions with people his age, and the occasional bouts of hyper intelligence he experienced whilst he messed about as grey matter. It made him unaccustomed to the occasional moments of immaturity his fellow students exhibited, and caused him to see certain very common social issues as rather inane and easily avoidable.
He still couldn't escape them if he tried, socially inept as he was, unless he spent all his time as grey matter, but he was trying to cut back on how long he spent as the small grey humanoid, it was seriously messing with his head.
One didn't just forget being a super genius after all, so it had a few effects on Izuku's mind that he'd ignored since they didn't particularly seem negative, but he was quickly realising that, thanks to the increased amount of time he was now spending around others, that it was seriously stunting his already terrible ability to interact with people.
"S-so, what did you want to talk about?" Izuku forced out, trying to break the silence, even though he was very sure of what Katsuki wanted to converse about, it was definitely about the thing he wore on his wrist at all times.
Izuku couldn't help but wince at the sudden return of his stuttering, honestly he should have paid for speech therapy or something.
"Your quirk, where the fuck did you get it from?" Katsuki asked in ironically quiet anger, which really only served to make Izuku more nervous than he already was.
The green haired boy felt the same as when he got in trouble with his mother and she just kind of looked at him in disappointment instead of screaming at him, it grated his nerves to no end.
Which was rather rare, since his mother liked to get quite vocal, and wash the entire floor and sometimes the walls with tears when Izuku got into trouble.
Not that Izuku was even considering likening his reaction to Katsuki's own brand of parental guilt tripping to that of his actual parent, it was just a weird analogy his anxiety addled mind was bringing to the forefront of his mind to distract him from the fact he was likely to have a scuffle with his classmate in the near future.
Izuku quickly produced the pre formulated lie he'd created to mask his sudden abilities.
"Turns out I've always had it, but I couldn't use it voluntarily, ten months ago it just activated on it's own, but I can't use it without this watch." The green haired boy said, showing his friend the black and grey contraption he usually kept under the sleeve of his uniform.
It was a different lie than he told his mother or Ochacko, because what he told them was the closest he could get to the truth without telling his mother and best friend that he had found some random, alien device on the floor and now literally showered with the thing on.
"Don't give me that bullshit Deku." Katsuki growled, grabbing the other boy by the collar, "I wasn't born fucking yesterday, quirks manifest at age four and no later, especially your mutant type quirk, that shit should have been around from birth."
Honestly, Izuku should have known that tricking Katsuki wasn't going to be easy.
"O-okay, okay, it's not a quirk, the watch takes care of all the transformations and the forms, but it's keyed to my DNA only, in fact the thing doesn't even come off, that's the truth, I swear" Izuku pleaded, he hated himself for it, hated how easily he had caved in front of the blonde, but no amount of pretending he was confident, and no amount of dickish comments could help him get over years of bullying and trauma.
He was just lucky he had managed to throw in some lies about his DNA that would hopefully stop Katsuki from trying to steal the watch.
"You swear it do you? Pray tell where did someone like you, find something like this?" Katsuki interrogated, baring down menacingly on the other boy.
"A family friend gave it to me to test it out, I'm helping him figure out some of the kinks." Izuku lied through his teeth, he was not happy at how he was basically being forced to reveal his secrets, even if he was lying, Katsuki fully expected him to just give in to his demands, and he did, like he had always done.
He'd played right into his hands, and that pissed the green haired boy off greatly.
"Well you better not be fucking lying to me Deku, or else…" the sentence went unfinished as Katsuki released a few threatening crackles from his palm.
That was the final straw.
That sound of small explosions that Katsuki had always used to threaten him when he was a child, a sound that heralded bruises and burns, many of which Izuku had yet to truly heal from.
Years of bullying, gone unchecked and unpunished.
Izuku clenched his fist in anger, the force he exhibited so strong that he could feel his nails almost breaking skin.
His anger was not only aimed towards his tormentor but also towards himself.
Things should have been different now.
He was strong now.
He had powers now.
He shouldn't be the one cowering and getting roughed up anymore, he should be the one stopping this kind of thing from happening, standing proud and protecting the innocent, but how could he save anyone if he couldn't even save himself?
How could he stand shoulder to shoulder with the next generation of heroes, his classmates, his friends, if he cowered and bent over backwards in front of a simple bully, villains would be much worse, because whilst Katsuki barely followed the rules, the bad guys didn't follow any rules at all.
Izuku looked at the blonde in front of him darkly.
His slowly reached up and grabbed the hand that was holding his collar, his grip tightening as much as it could.
Izuku relished in the look of surprise and hints of pain in Katsuki's eyes.
"Or else what Katsuki?" Izuku growled, sick of letting himself just be bullied. "You're going to beat me up?" The boy began pushing back against Katsuki's hold, much to the blonde's surprise. "I'm sick of you always pushing me around, thinking you're better than me. Things have changed you yellow porcupine haired bastard, this is U.A and last time I checked, not only did we both get a spot here, I scored higher than you in the exam." The boy's voice grew louder as he poured his grievances into his speech. "I'm not beneath you anymore, I'm no longer your punching bag, the roles have reversed in fact. Now I'm the strongest, I'm ahead." Katsuki's eyes widened at the surprising strength Izuku could exhibit without using his transformations and he felt himself actively have to push against the green haired boy in order to not get forced back. "This is a declaration of war you firework factory reject, the sports festival, me and you, sorting this out once and for all, until then I don't know you, you don't know me, try this shit again and I won't only hurt you, I will demolish you, consequences be damned."
Izuku let go of his former friend, emerald green that burnt with determination staring and startled and angry red.
"Do you understand?" Izuku asked coldly, activating his watch threateningly.
Katsuki paused for a second, disbelief marking his face, Deku had just stood up to him?
Him?
He'd called him inferior, he'd belittled him, he'd declared himself better than him.
Katsuki was as shocked as he was angry.
Deep down, however, he knew.
He knew Izuku was right.
The blonde had contented himself on the fact that his quirk was so versatile, that his ever growing arsenal would be able to compensate for Izuku's own seemingly infinite abilities.
But then he'd seen Izuku fly over the sand pit, not propel himself in the air like Katsuki did, which was as far as the boy saw himself going when it came to flying, but the green haired boy had actually flown, with wings, with a speed and stability that Katsuki couldn't hope to match.
That wasn't even all, because as it turned out Izuku had another form, and whilst the blonde hadn't seen the full capabilities of the dog like creature, he was willing to bet it had some bullshit power that Katsuki could never hope to emulate.
He wanted nothing more than to blow that stupid determined looked off the boy's nerdy face, but he relented that if boy transformed he would be hard pressed to beat him right now, which caused him a rather substantial amount of displeasure.
Ever since the slime villain incident, Katsuki's inferiority complex flared up with impunity, being humiliated like that, and in public no less, had not at all been healthy for the volatile cocktail of personality traits the boy possessed.
People redoubling this effect by asking him about it whenever they saw him had just made it worse.
Alongside the constant reminder of his weakness that was his throat, the event weighed heavily on the blonde.
What made it worse was the fact that Izuku, the worthless, quirkless reject, was making his complex flare more than the villain attack that had brought it to light.
That made Katsuki boil with rage.
Which in turn made him do something he knew was stupid.
"Okay, you fucking nerd, you think you can beat me? Then I'll accept your challenge, but if I win, I want you gone, I want you to drop out of U.A and go back to being the loser you've always been, instead of playing at being a hero." Katsuki growled, "How about it? Since you suddenly grew a pair of balls, are you brave enough to accept?"
Izuku smirked.
Katsuki could not believe his eyes, not a hint of fear nor hesitation, somehow the green haired boy had managed to piss him off even more.
"You know what, I accept." Izuku said coldly. "But, if I win, I want you to drop out, after all, if you can't even beat a useless Deku, then what use are you as a hero?" Izuku countered.
Katsuki knew the greenette would counter him like that, and the problem was, he wasn't fully sure he could beat him as he was now, not without spending every waking moment training, and he knew that Izuku was likely bitter enough to find a way to force him to follow through on the bet if the blonde lost, because that was exactly what he would do to the green haired boy if the shoe was on the other foot.
Katsuki had trapped himself into a corner, and he knew it, but backing out now was unacceptable, he needed to cling to the remainder of his pride.
So he simply snorted in annoyance and brushed past the other boy violently.
Leaving the room after slamming the door as violently as he could, hoping the loud noise somehow translated to him winning the argument they just had.
As soon as the blonde had left the room, Izuku practically melted into a nearby chair.
He had just agreed to something stupid and he knew it, Katsuki was strong, probably stronger than even the blonde himself knew.
Beating him in a full on fight would be difficult, but Izuku knew Katsuki's quirk probably better than he knew his own powers, in fact, he probably knew them better than their own user, so he knew what was needed to counter his old childhood friend.
In fact, the boy would go so far as to admit that he had the perfect form for the job, but underestimating Katsuki was a poor choice, the blonde was the worst and best kind of person when it comes to this kind of thing, arrogant and stubborn, which made him very hard to deal with both in the social sense, and in the combat sense.
Izuku knew his ex bully would train himself to the bone to be proven right, and he was sure Katsuki had never actually done that before, since the boy viewed himself as a genius he probably coasted through life by working just as hard as he thought he needed to.
Now the greenette had probably convinced him that how hard he needed to push himself was a lot harder than it was before, which Izuku supposed was good, his entire goal for being a hero was to set an example and force other heroes to work harder in order to catch up.
If only he hadn't staked his career at U.A, he could enjoy the moment more.
For now he needed to beat Katsuki, and the only problem he could think of was that the sports festival spanned hours, and the last competition was always tournament brackets, which would be continuously more straining on his transformation time, so the later he got to Katsuki, the less time he would be able to stay transformed.
What he needed now was to boost his transformation time, and probably give his forms a quick tune up combat wise.
The only way to do that was to train.
To beat Katsuki he would need to train more than anyone.
The boy didn't want it any other way.