Chapter Text
Most people mistake Bakugou’s bristly personality as indifference and often people make the stupid-ass assumption he doesn’t know things about people. Like when Mina thought he didn’t know Kirishima and her went to the same middle school. Of course he knew that! He had ears damn it.
And that was the thing. Bakugou may not care to know about people’s business on the surface level, but he was paying attention. These were people he was going to compete and work with as heroes. It was beneficial to know things.
Like the fact that he knew that Mina helped Kirishima dye his hair. Or that he knew that Denki pierced his own ears the summer last year. Or that Sero’s been using Yaoyorozu’s note organization method since first year.
Now those were his friends, so of course he knew about them. However he paid attention to others in his class as well. Like how Frog Girl and Round Cheeks hung out a lot. Like a lot. He didn’t think they were dating yet but maybe. Or how Rocket Legs was working on mastering the techniques his older brother had used as a pro, and was making good progress. Or how Icyhot has been going home to visit family more now and he seems more active in ‘class social time’. Or how Aoyama was doing better at the new technique he modeled after the nerd’s air-shoot style.
But for all the observing Katsuki did of others around him, there was one person in particular that he paid the most attention to. Of course he had given attention to watching the nerd before they started at U.A. but it was more out of frustration for the nerd’s stupid determination. But once entering U.A .and pissing Katsuki off with a sudden quirk acquirement, he paid special attention to the green haired boy.
And then all the shit with their first year happened: Deku never backing down from trying to stand next to him, the nerd transforming the meaning of his nickname to his hero name so he wears Deku with pride, their emotional fallout after All Might’s final fight. At first Katsuki thought his observations of the nerd was just the occasional observation to keep an eye on his rival. Then, slowly, Katsuki realized these observations were intentional. He watched the nerd carefully.
In his defense Katsuki swears it was purely rival based. He was keeping track of how the nerd developed his quirk. He took mental notes on how the nerd stole and adapted his own moves. Then once he finally understood Deku better after their Ground Beta fight, he would check in on the nerd and comment how else to use a skill. It was all to help the nerd catch up. Like Almight said, they were growing at different levels. That had only made Katsuki want the nerd to catch up, see what he was like at his level. The thought was exhilarating.
Now at some point between keeping a training-focused watch on the nerd and now, slowly Katsuki started to notice the personality changes too. This Deku was transforming into someone so entirely different than the boy he grew up in proximity to. At first he watched closely out of suspicion but slowly he found it growing into a curiosity and eventually Katsuki found this new Deku interesting so he kept a closer eye. Where Deku had never really had friends before, now it seemed he had the entire class wrapped around those scarred fingers. He still had moments of intense anxiety that mirrored his awkward middle school self, but it had mostly been replaced with someone who built their confidence and worked their ass off to be at the top. Where once he would only timidly add to a conversation he now engaged with others with bright smiles. The best part of this transformation was Deku’s newly acquired lightning-fast sass. Katsuki found it immensely entertaining.
The first time Katsuki can recall witnessing it, it had been directed at Mineta and it was something along the lines of “If the girls can’t make you shut up, I happily will.” And it had Katsuki quickly turning around and stifling his snort into his hand. It sounded like something he would say! Mineta’s face was priceless.
The first time the sass was directed at him Katsuki discovered something. It was in the middle of a training assignment at the end of their first year and it had done something funny to him. They had been put into groups of threes and they had to stealthily sneak into a building to ‘save hostages’ before taking out one of the teachers who were posing as a villain. He had been placed into a group with the nerd and Kirishima. Which was stupid since they all were incredibly offensive based heroes.
They had been debating how to enter the building since all the doors were locked and Ectoplasm had clones at every entrance. Except at the roof.“Let me blow the lock on this door. Then we can be in and out.” Katsuki said as he reached for the door with his palm already sparking. A solid weight fell onto his gaulet, pushing it down. He looked down and saw Deku’s gloved hand there. He quickly looked up and saw those green eyes looking at him with something like…judgement? What the fuck?
“An explosion. Great idea for a stealth mission Kacchan.” Deku deadpanned at him before turning around. Katsuki could of swore he heard “God Damn.” under the nerd’s breathe before he spoke louder. “Follow me Red Riot. Let’s see if you can cut glass.”
Katsuki had immediately felt the shock at that comment and he felt his face and skin heat up. It wouldn’t be until they are done with the assignment that he would realize it wasn’t anger he felt. It had been closer to the blood-rushing feeling he gets when Deku joins Bakugou and Kirishima during training. Like when he sees Deku’s eyes flash with that passion as he activates his quirk.
“Ah he’s got the Midoriya look again.” Kirishima’s stage whisper whipped him out of his thoughts.
“EH? The fuck did you say?” Bakugou turned to look at his best friend.
“The Midoriya look.” Mina clarified. “You know that feral smirk you get when start thinking of Midoriya.”
“There is no Mid- look for that nerd. I don’t even think of the nerd.” Bakugou had stopped himself from saying his name out loud. He knew his friends would flip their shit if he used it. And personally it felt weird to use it out loud. Not in a bad way, just…different. And Katsuki wasn’t there yet.
“Ah come on dude.” Kirishima bumped his shoulder.
“I mean we can’t blame Bakugou guys.” Sero jumps in from across the table. “Midoriya has those big kind eyes, that bright smile, and those thighs!” Sero sighed dramatically as he looked across the cafeteria.
“Hey! Quit thinking about the nerd’s thighs!” Bakugou exclaimed as his face heated up.
Sero gave him a salute and a “Yes Lord Explosion Kills!” as his friends broke into laughter.
And now a week later he wanted to wring Sero’s neck. Now there is yet another thing that Bakugou is noticing about the nerd. And just like the sass this new thing makes his blood boil and chest heave with excitement. Like he wants to fight Deku.
And that new thing is Deku’s god damn muscles.
After their lunch conversation, Katsuki had been furiously curious as to what Sero meant. The nerd was a runt and last he checked scrawny. So at the next training session for class he tried to discretely watch the nerd out the corner of his eye. Now Katsuki will admit, the nerd was strong and for him to be that strong there meant there had to be some muscle right? So that made logical sense. But it still didn’t correlate to Sero’s comment which had been bouncing around in his head for a whole day now. It didn’t make sense until the next day when they were all in full hero costume and heading to a training ground.
The nerd was up at the front with Rocket Legs probably chatting about how they were going to get graded. Ugh, he almost groaned out loud. He knew the nerd so well he knew exactly what he would talk about. But then Bakugou’s eyes took a moment to make another observation of the nerd’s body. Yeah he was strong but now that Bakugou looked closer, the shrimp wasn’t- well a shrimp.
Deku’s arms were well defined even in the suit. It wasn’t like it was a skin tight suit. But since when did Deku have biceps? Or traps? They were nothing like Bakugou’s own arms, since he had been focusing on them since childhood because of his quick, but the nerd definitely impressed him.
His eyes traveled lower to his legs. It was expected that Deku’s legs had built muscle with the endurance training they do let alone the individual work he does for his kicks. But unlike the arms, Deku’s legs very much filled out his costume and despite the pockets and add-ons that bulked to suit, Katsuki could still see the powerful muscle moving under the fabric.
“See what I mean?” Sero’s voice was so close to his ear that it scared the shit out of him.
Bakugou whipped to his left, palms already exploding as he reached for the laughing moron already swinging away on his tape. “Get back here you tape bastard!” He shouted after him.
“Tape bastard?” Sero called as he swung to a nearby building. “That’s basic even for you? Is the Great Lord Explosion Murder off his game today?”
“The Fuck?” He shouted angrily running ahead of the group to catch that bastard.
“Guys we need to keep a close eye on Bakubro today, he’s in his feels!” Sero shouted at their group. Unfortunately it was loud enough for the whole class to hear.
Bakugou was definitely going to kill him when he heard the nerd start mumbling under his breath somewhere behind him. He was about to turn around when Aizawa showed up got them to work for the day. For the rest of the day Katsuki watched Deku out the corner of his eye and stubbornly did not name the feeling that made his chest feel constricted.