Deku's probably in denial about the way his body has... changed, but Katsuki still doesn't think that's a good enough excuse to continue wearing clothes that are evidently too small for him. Then again, it takes Deku splitting his seams /six/ times before Katsuki does something +

about it. Maybe Katsuki's in denial too, about how attracted he is to the way Deku's curvier, but more toned too, with the confidence that comes alongside an improved body. Maybe that's why in the first five incidents, Katsuki does nothing.
Well, maybe the first time doesn't +

count. Katsuki isn't the only one watching when Deku's sports uniform splits down the middle, exposing his underwear. No, the entire audience at the Sports Festival is witness to it too, and Katsuki is too busy staring at the bright blush on Deku's face as an interval is hastily+

called to sort the situation out. Katsuki strides to the waiting room, where Deku's changing into a spare, better-fitting uniform, intending to see how his friend is faring. It's one of the many things that have changed since the first year. Whilst they still have their own+

friendship groups, Katsuki and Deku spend as much time together possible outside class, whether it's playing video games or sparring, or even studying together. Maybe that's why Katsuki ends up being privy to so many of Deku's wardrobe mishaps, but in his mind, the first time +

doesn't actually count. Deku is silent as he gets changed, a faint red still smattered across his cheeks. Katsuki doesn't say much when he enters, sitting on the bench and mumbling, "you okay?". Deku nods, and Katsuki trusts him. Plus, he must have been telling the truth, +

because he ends up beating Katsuki in the final round, something that Katsuki promises to get even for. (They delete any footage of Deku's accident afterwards, but Katsuki never forgets that blush.)
It's whilst he's "getting even", aka sparring with Deku, that the second +

incident takes place. Deku's in gym shorts and a tank top, and Katsuki's already been distracted by the way the flimsy material rides up to bare Deku's round ass. But then Deku goes in for a roundhouse kick, and as Katsuki grabs his leg, flipping Deku over face first onto the +

floor, a resounding /rip/ echoes through the empty gym, and Katsuki looks down, where... Oh. /Oh/. Deku's legs are wide apart, ass in the air in the awkward position he landed in. But suddenly it looks very appetizing, because there in front of him is Deku's exposed ass, his +

underwear doing nothing to hide the smooth curve (considering it's wedged between his ass, evidently a few sizes too small) of Deku's skin. The shorts are little more than two ripped pieces of fabric, because as Deku stands quickly, mortified, the fabric gives further way, his +

ass pushing out in a way that makes it look bigger than it already is. And considering how /round/ Deku's ass is, that's a feat. Katsuki's still trying to figure out a way to segue back into their sparring session when Deku squeaks out an apology and flees from the room. Tch. +

The third time is definitely the most hilarious. In Katsuki's opinion, anyway. Or perhaps he's passing it off as hilarious because he's actually /really/ fucking turned on. It's the school culture festival, and for their last year, the girls have taken the reins and demanded a +

reverse maid cafe. No, that's not quite right. It's /Kirishima/ who says they need a spin on the list of their ideas, and as maid cafe is at the top with the most votes, Kirishima mentions "reverse", and suddenly the girls are /insistent/ that they do a reverse maid cafe. Not +

only does it save them from wearing frilly maid outfits in front of Mineta (who somehow has made it this far), but Katsuki's sure that the girls just want to see Deku in a dress. They've tried and failed multiple times, and Katsuki scowls at all the attention he's getting. More +

specifically, he scowls at all the attention Deku /gives back/, especially to Round Cheeks. He respects Uraraka in general, but when it comes to Deku, the very sight of her near him makes his blood boil. He's spent so long rebuilding his friendship with Deku, and she comes +

along and sweeps him away from Katsuki whenever she wants. So he's jealous of the friendship. That's it. /Anyway/. They're in public again, so technically this time doesn't count either, but whatever. Deku's serving some students from class 3-B whilst Katsuki loiters behind, +

refusing to serve his sworn rivals. Deku bends over to pour some tea, his skirt hitching up just enough to tease
Katsuki. Still, he's wearing tights, so his ass is somewhat covered. That is, until one of the students "drops" a napkin and Deku reaches down to pick it up. +

Maybe it's because it's happened before, or maybe it's because Katsuki sees the pervy glint in the student's eye, but Katsuki knows what's about to happen and steps close behind Deku, blocking his ass from view just as the young hero's tights tear, his ass bubbling out from the +

various new holes in his tights. He stands up immediately, clutching his ass even though it's covered by the skirt again, and almost knocks into Katsuki.
"Oi," Katsuki says, placing his hands comfortingly on Deku's shoulders. "Go get another pair from Momo." Deku nods and runs +

out of the room, too embarrassed to speak. As soon as he's gone, Katsuki rounds on the student.
"Get the fuck out, you disgusting perv!" he shouts, grabbing the student by his collar. "I saw exactly what you fucking did, you creepy piece of shit. I don't wanna see your face +

around him again, and I sure as hell don't wanna hear you've done anything else gross."
The student is protesting the entire time Katsuki's yelling at him, but when Aizawa comes over to see what the commotion is about, he gulps and nods, scurrying out of the room. His friends +

stay, save one or two who have gone with him, and one of the remaining students sneers at Katsuki.
"Overprotective much? You'd think he was your boyfriend or something."
Aizawa has to break up another fight a few moments later, and the snarky student is kicked out too. His +

words stay in Katsuki's mind, though. Deku? His boyfriend? Why does that send a spike of warmth running through him? He thinks about it for the next few weeks, but the answer, that he has a /crush/, doesn't come until the fourth incident, whilst they're playing video games.

(tbc at some point in the next few days? I've wanted to write this idea for a while but now that I am, it doesn't seem to be flowing properly, the writing seems a little clumsy... What do y'all think?)