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Mini Nerd

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It had been three weeks since Deku had offered his help on the case. Of course, he didn’t need that shit face’s help, but it was a little nice to have his over analyzing eyeballs on the problem. Things just kept turning up missing out of the vault of one bank, which was monitored by a woman with a surveillance-type quirk. Apparently, she could feel the heat signatures of someone who entered a determined space she could choose. She would notice a large cold spot, too, so it wasn’t that.

Within a few minutes of entering the crime scene, Deku had come up with the theory of a shrinking quirk, like the opposite of Mt.Lady’s. That explained the bypassing the quirk, but not how they were getting out with the goods.

So they’d been staking out the area in turns between their patrols, assisting the cops as hero backup. Why they’d asked Bakugou first, the guy who blew shit up, to stakeout a fuckin’ vault of people’s personal shit, he will never guess.

Nights seemed later on the stakeout. There was, like, regular night where people went to convenience stores and the party scene, and then there was real night. The only people at stores were the employees and that weird guy. The bars and clubs had closed. Lights went out. Even the stars seemed brighter after that time. The air smelled cleaner. Instead of exhaust and booze, the air was fresh, just coming in off the sea. Of course, the whole scent of the area changed when Deku showed up.

Deku smelled like sweat and ozone, as though the green energy around him was actual lightning. Or maybe it was because he jumped so high? Doesn’t matter, cause this time the nerd had brought donuts.

“Anything happening?”


“Mind hanging out with me for a while, since you don’t have patrol next?”

“And cut into my sleeping time? God, you’re selfish as shit!”

“You don’t have to. I just wanted to talk to you.”

“Mmn.” Bakugou sat back down on the rooftop, relaxing into the same seat he always took- perched on the ledge, ready to jump.

Deku sat beside him, opening up the donuts and offering him one. It looked to have some sort of frosting on it.

“The fuck?”

“Cinna-” the building had changed slightly, and both of them noticed, leaping directly into action, donuts put aside.

Deku was there first, since Bakugou had to slow his momentum before he hit the ground too hard, and turned the corner into the alleyway. It didn’t take even a second before Bakugou was there, but the weird blueish flash of light was concerning. The perp was the size of a mouse, caught in Bakugou’s hand faster than he could even register the size. Another blue flash of light and he found himself wrestling a normal-sized man to the ground, watching necklaces and coins spill from the pocket of his jacket. Cuffed and in custody, mouse-shit wasn’t gonna do anything anymore. But where was Deku?

After the police had Mouse-Shit (Bakugou had decided not to learn his name) Bakugou went back to the alleyway and started looking around the garbage bins. He was not concerned for Deku, no matter what anyone said. He just knew that losing his partner after this simple takedown was going to bring more bullshit to him.

“Show yourself, Shitty Nerd.”

“Over here!”

Another tiny entity waved his arms wildly from where he was near some tied up papers. Deku was now about three inches tall. Bakugou crouched beside him to get a better look. The bright light and combustion of his explosions was wrecking both his eyes and ears, so Deku was more than a little blurry.

“What the fuck did you get yourself into.”

“Sorry, I slipped up. Can you take me to the police out there? I think I need them to take me home.”

“I got it.” Bakugou plucked him up neatly by the back of his suit and tucked him into his thigh pocket. “Brace.”

Deku braced just in time for Bakugou to send them rocketing into the sky. While he was used to the g-forces involved in his own movement, he was not prepared to be moving so fast relative to his size- not to mention the heat and caramel-sweet scent of his burning sweat. Deku’s scream pierced the night, far too high-pitched due to his tiny vocal chords.

Like a dancer, Katsuki launched them through the clear night air. His explosion of hair moved only a little with the movements, despite how fast they were. That’s thick hair for ya. Bakugou’s quirk had them back at Midoriya’s house in minutes. He climbed into the unlocked window and flicked the lights on.

“Oi, shitface, clean your apartment more often.”

“Yeah, I knew you’d say something like that.” Deku sighed.

Kacchan set the tiny body on the counter of the kitchen and sat down at the barstool.

“You don’t have to stay, if you don’t want to.” as he absently cleaned his plate, despite his size.

“How’re you gonna get to the bed? Or your toilet?”

“I can jump!”

“And tear your house up with your shitty craters everywhere?”

“...” Deku couldn’t find a better argument that wouldn’t send Bakugou into a spiral of rage.

“That’s what I thought. What do you have here to eat?”

“I have some cup ramen?”

“Oh fuck you.” Bakugou rolled his eyes and walked to the door, “I’ll be right back.”

Which left Deku with his dirty dishes and a lot of cleaning to do. He kind of enjoyed it, actually, because he could clean a lot more thoroughly. Those little cracks around the screws of his pan? Clean. The weird rim of his water bottle? Clean now! Just when he started having fun, and testing one for all on his new situation, Bakugou returned. He was burdened with a few grocery bags from the convenience store down the street.

“They didn’t have any good produce, but I found enough to actually make something.”

“Welcome back?”

“Shut up. Give me that.” He picked up the pan and started heating up something from the groceries, and in barely a second of the sound it smelled amazing.

Bakugou picked Deku off the counter and set him on the floor.

“Go sit down somewhere. Your lungs are tiny now.”

Deku nodded and crawled up onto one of his lumpy throw pillows. It was, surprisingly, very comfy for someone so small. The remote felt like it was a mile away. With a few deep breaths, Deku fell asleep.

Bakugou cooked up some rice and curry, figuring that would be easy to separate for a small portion. He used Deku’s plate for himself and poured a small amount on a tea saucer. He carried the servings into Deku’s living room and set the plate beside the sleeping tiny form.

“Wake up.”

Deku started, then calmed down when he saw it was Bakugou. He rubbed his eyes, then looked to the serving on the tea saucer.

“Woah. Thanks, Kacchan!”

“Zip it. Eat.” Bakugou sat beside him on the couch and started eating his own food.

They ate in silence. It struck Deku as a strangely domestic comfort, that they could stay silent in his house without fighting. Despite the years, he was still worried Kacchan hated him. Obviously, Kacchan no longer seemed to want him dead, but he still didn’t know if Kacchan would call them friends. It’s always been complicated for them.

“You done?”

“Yeah, sorry. It’s a big portion for this size. It was delicious!”

“Keep your tiny mouth shut.” Bakugou grabbed the saucer and carried them into the kitchen.

Deku pushed his hair back and took a few deep breaths. He crawled off the throw pillow and dropped to the floor, trying to figure out what of his nightly routine he could even do. Working out was mostly out. He was too small for the reinforced equipment he had. Bathing seemed insurmountable at this size. There really wasn’t much he could do at all.

“Hey, any word on how long this might last?” He called to Kacchan.

“They’re looking at about 24 hours. It’s just an estimate, though.”

“Ah. Thanks!”

Bakugou placed the dishes on the counter and paused. This was gonna have to work. He walked to Deku’s bedroom and grabbed some clean clothes, a shirt, sweatpants. Nothing fancy, all stuff he’d borrowed from them when they were kids. Deku liked soft clothes with dumb print, nothing like his own stretchy shirts.

“Get on my hand, tiny.”

He held his hand out, palm up, low to the ground, so Deku could climb on and get comfortable, so he could have control of how he was carried. Deku did.

“Where are we going?”

“Taking a bath.”

“Wait what?”

“You still use that same shampoo, right?”

“Well yeah.”

“Taking a bath. You can’t have one by yourself.”

Deku buttoned his lips. Kacchan had determined what he was going to do and was going to do it. No point in arguing. Bakugou set him on the counter and started stripping. After rebooting his brain, Deku turned around and stripped off his hero costume. It was comfortable, but wearing it for so long had left red marks around the belt and upper thighs from the harder guard materials. He sighed and rubbed his thighs smooth, sitting on the cool counter for a moment while Bakugou ran the bath.

Observant as ever, Deku took mental notes of Kacchan’s increased muscle mass and the suntan from his mask. Bakugou had always been built like a dancer, with lithe muscles best suited for flips and leaps and the range of mobility his quirk allowed. Well, he’d been built like that since highschool. When they were littler, they were both little chubby kids. Deku shook his head at the thought of so long ago, when he and Kacchan were still friends. Before middle school, they had seemed a lot like friends. At least, Deku thought he was Kacchan’s friend. In middle school, their relationship had gotten worse. Then, in highschool, it kind of got better, but it hadn’t changed since.

Bakugou sat down and showered himself clean before getting into the bath, then wet a washcloth and plucked Deku up.

“Let go of me!”


With his hands he scrubbed Deku’s tiny body. The washcloth was big enough to cover his entire body (save his head), so he didn’t even think about Deku’s body. Nope. Not one bit. Not the powerful brick wall of a body Deku had, that, while so strong and sturdy, was still dotted delicately with freckles and blushed around his joints. Not that he could feel the soft squish of such large muscles through the cloth, either! He wasn’t thinking about him. At all.

Ok, maybe he was wondering how they’d ended up like this. Not, in the bath together, that was all completely logical given what Deku’d been hit with. No, he was wondering how he’d gotten to the point that he couldn’t voice his affections, even alone. He’d wanted to protect and care for Deku since he’d learned his best friend was quirkless. He’d known he had more than enough power to do that since he’d gotten his own quirk. But it was always All Might, All Might, All Might, with Deku. He sighed and looked at Deku, who he’d scrubbed red by now, and squinted.

Deku was special to him. He talked a big game, because it always felt like Deku was talking down to him. Deku was smart, especially about heros, and he made Katsuki feel like he wasn’t enough of a hero for him, or that he was doing something wrong, but he had spent the last couple years now in therapy. Court-ordered, every two weeks, with some side anger management courses, after he’d cussed out a few survivors who were refusing to follow him out of the collapsing building. They’d all been adults, and they’d all been being idiots, but one of them had enough money to sue the hero agency. But that didn’t matter, what mattered was that he had yet to say something to Deku that was positive.

“Are- are you done now?”

“Not yet.”

Bakugou took the wooden soap holder and floated it on the bathwater, then got in, then set Deku in the soap holder, which had half-flooded with water, so it was a nice shallow bath-boat for him.


“Yeah, yeah, I’m a genius.”

“You really are, Kacchan!”


Bakugou leaned against the side of the tub, taking deep breaths and letting the tension seep out of his muscles. Deku laid in the shallow water and looked over to Kacchan.

“You’re being nice to me today, Kacchan…”

“No I’m not.”

“Yeah you are. Thank you.”

“Someone had to make sure you would take care of yourself.”

“And you wanted to make sure I did.”

“Not like anyone else knows you so well.”


“People know you’re a shitty tryhard, but they don’t know how stupid you really are. You’d have made it back to your agency eventually, but you wouldn’t have come home, just tried to write your report.”

“Hah. You’re probably right.”

“How were you planning to sleep?”

“I was just going to climb on my bed.”

“I’m sleeping on your bed.”

“Uh. I guess I could just sleep on a towel or something?”

“Yeah that might work. As long as you’re comfortable.”

“You care if I’m comfortable, now?”

“Comfort is necessary for good quality sleep.”

“Nah, you give a shit, Kacchan, admit it.”

“Shut up.”

Bakugou shifted his weight and leaned in close, looking at the little boat Deku was on. “You’re stupid.”


“And nerdy.”


“And useless.”

“You’ve always said that.”

“‘Cause I’m fucking right.”

Deku laughed in his chest, smiling up at the huge red eyes of his oldest friend.

“I’m starting to wonder if you believe all that.” He almost whispered.

“Yeah, I do.”

“If you really thought I was a shitty, useless nerd, you wouldn’t accept me as a hero, much less
as a partner in battle.”

“Shut up.”

“I’d even wager you saw me as a useful, productive hero, if not a good one!”

“I said-”

“And I think you care about what I say. Something you could blow off from anyone else you seem to react more to from me!”

Bakugou grabbed Midoriya in one hand, clutching him tight just out of the water. His face was scrunched and sharp in anger, but it was also as red as a rose.

Deku gasped for breath, squirming in his grip.

“I said shut up.” He growled, “ I said shut up and I meant it. You’re more of an idiot than I thought.”

He loosened his grip on the tiny hero, then surged out of the bath with him and dried himself off. He set Deku on the counter so he could get dressed, and Deku, a little dizzy, couldn’t react before he was back in Bakugou’s hand.

“Woah! Let me get dressed!”

“There aren’t any pjs your size right now.”

He carried Deku out into the living space and then to his bedroom, where he crawled into bed. It smelled so much like Deku in here. It was perfectly set up for the shitty nerd to do his hero analysis at his desk and workout in the corner opposite his bed. He set the little naked Deku on his chest and laid back, sighing.

“Are you mad that I’m wrong or because I got it right?”

“Not mad.”

Deku snuggled into his shirt, relaxing with how he rose and fell for each of Kacchan’s breaths, settling into the sound of his huge heart beating.

“You’re really warm.”

“Yeah, dumbass, they found my internal temperature is slightly higher than average when they took a closer look at our quirks in third year. You wrote it down and everything.”

“It’s probably to help you sweat more, and might even be a result of your hero conditioning.”

“Yeah. You muttered that out.”

“You listen to my muttering?”

“You say a lot of useful shit when you’re writing.”

Deku rubbed his hand on Kacchan’s chest, smiling to himself. “You’re kind of cute.”


“No, I mean, you’re…. Really sweet.”

“Shut up. Go to sleep.”

Deku pushed up off his ribcage and crawled up to settle on his neck. It was warmer there, and it was thinner skin, he could feel each beat of his heart loudly from his jugular.

Katsuki had not slept with someone in the same bed in a long time, and even this tiny little form seemed like so much. Deku was here, he was so fragile, so much alive. Not to mention, Strak fucking naked. He fell asleep quickly with the weight on his neck.


They woke up more confused than they needed to be. Deku was full sized again, naked, and cuddled up to Kacchan. Katsuki woke up second, but held Deku every second he was asleep. Tangled legs and rough hands on scarred skin melded into the smell of their morning breath.

“Mnf… Kacchan.”

“Hmm.” Bakugou took the time he needed to think about this. There was no way that was 24 hours. He nuzzled his nose into the green hair.

“Uhm. Wait. Bakugou?”


“Can you let me go get dressed?”



“Nope. You’re gonna lay here, right beside me. Naked as the day you were born.”

“Oh come on, if this is a prank, you’re taking it way too far!”

“Hmm.” Bakugou’s hands felt up the scars on Deku’s back to his spine, brushing his fingers gently up the center dip. Up the spine, then back down just as slowly, to come to rest on his ass.

“Uh!” Deku shivered, then tried to relax. It was just Kacchan being a jerk. Or something.

Bakugou closed his eyes and relaxed. Deku was soft and warm and just everything he could’ve dreamed. Now that he had the nerd like this, it didn’t feel right to let him go. At least not before he’d marked up the freckled skin all he wanted.

When Bakugou finally went in to kiss Deku’s neck, he pinned him down by his wrists. Deku barely resisted, kind of because he didn’t want to hurt Kacchan, and kind of because he was so caught off guard. His cry of confusion melted into one of pleasure, but then he pulled his right hand free to cover his mouth, red from his hair down to the top of his neck. Kacchan’s teeth scraped at his skin and he whined, trying to get his legs free.

Katsuki laved his tongue over the red streaks from his teeth, growling. Then he felt a kick from below him.

Deku pushed Kacchan off by his hips, with one foot, forcing him to lay on his side. He grabbed the side of his neck that Bakugou had bitten and sat up. Red, sweating, and more than a little roughed up, he turned to his attacker.

“Fuck you, Kacchan! I don’t care if you want to tease me, but that was just too cruel!”


Kacchan bared his teeth, getting up into one of his many launching poses. Deku, knowing exactly what was coming, wrapped a leg over his hips, knocking him on his ass on the bed, then pinned him by his shoulders and hips. Consequently, he sat right in his lap.

Bakugou’s eyes got wide, then his smile did.

“Who said I was teasing?” He rocked his hips up against that plush ass.

Deku immediately fell apart feeling what Kacchan meant, yelping and sitting rigid, startled into sitting up. “Ah!”

Katsuki took that as a cue to sit up himself, capturing Deku’s shitty lips with his own. He kissed him firmly, pressing his tongue into the back of Deku’s mouth. When they pulled back to breathe, he grinned like a shark.

“I’m not fucking teasing you if I really want to fuck you, right?”

“Ah… but, don’t you… uhm. Think I’m stupid?”

“Wanna know some shit?”

“Uh, what?”

“Never wanted to sleep with anyone else, and to be honest, it’s really hot knowing I can’t break you.” He brushed the tip of his tongue over his canine.

“Oh my god, Kacchan.” Deku couldn’t look in his eyes.

“Oh, like you weren’t just waiting to be seduced by me. You’ve liked me since we were brats.”

“Admiring you is different than this!”

“So you don’t like this?” Kacchan raised his eyebrows.

“I didn’t say that!” Deku scrambled a little to deny that.

“So, you admit that you like me?”

“I didn’t say that either!”

“Well do you mind if I mark up your neck for a little while longer, Deku?”

“No, I mean… I guess not… if you really want to.”

“Then relax and let me do this. And speak the fuck up if you don’t like something! I’ll kill you if you just lay back and accept shit you don’t want.”

“Oh-Oh kay, Kacchan.”

Bakugou nodded and gently laid Deku on his back among the pillows, then peeled his shirt off. He leaned down into Deku’s neck again and kissed him on points on his neck that he knew were sensitive. It felt completely natural for him to shower Deku in attention, in marks that showed who the fuck he belonged to, in heavy breaths and in his sweat.

Deku held back moans in his throat, stretching out under him and linking his ankles behind his back. He was more than a little confused, but honestly it didn’t feel wrong for Kacchan to have so much access to his sensitive spots, to things he’d usually hide from everyone. It was really weird to know Kacchan was excited about his body like this. He couldn’t deny thinking Kacchan was hot, especially when he was holding him down and working his neck and chest with his tongue. He drew in a shaky breath.

“I can and will fucking love your shitty person, Deku.”

“Uhm. Is that a threat?”

“Yes. You’d better be prepared to accept all my feelings, you jerk.”

“I- wait, Kacchan? You like me?”

“Think I’d be doing this to someone I didn’t like?”


Kacchan buried his hands into Deku’s soft curls, rocking his hips down against him. He kissed his mouth again, teeth and tongue and boiling lust for Deku spilling into him. He knew he was a great kisser, and he pulled out all the stops to impress him.

Not that Deku could tell. He was a little lost in all the sensations Kacchan was carving into him. He didn’t know if he would ever forget the feeling of Kacchan’s hard dick against his own, or the way his tongue seemed to dance around his mouth, leaving him breathless and starving for more. He felt Kacchan bite his lower lip and suck on it before he pulled back.

“God I want to fuck you.”

“Please shut up, Kacchan.”

“I mean it.”

“Lemme try something.” Deku’s eyes came into focus and he surged up to bite Kacchan’s neck.

Bakugou moaned, then absolutely growled, pushing his sweatpants down.

“You shitty nerd! If you weren’t…”

“Weren’t what?”

“ Weren’t so woefully unprepared, you shit goblin.”

Deku laughed, then reached over to his nightstand drawer and pulled some items out.

“What’s so funny.”

“Here, just. Look.”

After a quick inventory, water-based lube, condoms, a dildo. Shitty nerd was not as innocent as he’d thought.