Katsuki wiped a trail of blood from his chin, cringing a little at the sting of his cut lip. As far as battle scars went, it was one of the more minor injuries he'd had so far in life – then again, he was still in high school. As he looked around to survey the situation, checking for civilians who might need help or villains sneaking up on them, he couldn't help but notice that something was... missing.
His head whipped to the left, looking for the source of the familiar voice that had somehow sneaked up on him, but he was met with thin air.
"Um, I'm... down?" the phantom voice continued.
Slowly Katsuki shifted his gaze, tilting his head until he finally found the tiny figure. He was maybe the size of Katsuki's hand, like one of the squishy little All Might plushies that Izuku liked to hang from his bags, and Katsuki could feel the disbelief in his face as he squatted down to take a closer look.
"I guess that villain shrinks things?" Izuku offered nervously, his voice a little squeakier than usual. "I'm sorry to ask, Kacchan, but do you think... Um, maybe you could..."
"C'mere," Katsuki said knowingly, wrapping a fist around the tiny body and lifting him up. "Wonder if I could flush you down a toilet."
"Kacchan!" Izuku protested, squirming desperately in the strong grip. "Don't be mean!"
"I'm a hero, nerd, not a murderer."
Katsuki reached for his bag, discarded to one side when the commotion began, and Izuku squawked at him again when he tugged the zip open.
"What?" he demanded, pulling his phone out with his free hand. "Shut the hell up."
"I th-thought you were gonna put me in your bag," Izuku admitted. "It was uh, scary."
"My bag is scary?" Katsuki snorted. "You're the size of a fuckin' teddy bear in a world of supervillains, and you think my bag is scary."
"I don't know what's in there, Kacchan! And It's dark!"
"You're so fuckin' stupid."
Izuku pouted, but then Katsuki was tucking his phone in his pocket, holding Izuku up to contemplate him.
"So what am I meant to do with you, huh? I'm not just gonna carry you in my damn hand the whole way back."
"Hmm... I could sit on your shoulder?"
"Like hell. Think I'm gonna sit on the train with a stuffed animal on my shoulder?"
"I'm not a toy!" Izuku pouted. "Will you protect me if I sit in your pocket?"
"You think I'm gonna let you get squished or some shit?"
Katsuki snorted, but nodded all the same, sliding Izuku into his blazer pocket. He could feel the nerd squirming, finding a way to get comfortable, but by the time they reached the train station he had finally fallen still. Katsuki kept his bag on the same side, a little extra buffer between passers-by and the tiny figure in his pocket, and when he sat down on a quiet train he let out a breath he didn't know he'd been holding.
Babysitting was tough.
He pulled his pocket open to look inside, to let the nerd know he was safe to move around if he needed to stretch or readjust, but when he saw the fluffy green hair and freckled face resting against his body, eyes firmly shut, he closed his mouth.
At least it should keep him quiet for a while.
When Izuku woke up, he was surrounded by the softest blankets, enveloped by the warmth they brought with them. He blinked his eyes open on a dark room he didn't remember entering, yawning as he sat up and rubbed his eyes.
"Where am I?" he mumbled, climbing to his feet and immediately losing his balance. "Hello? Is anyone there?"
The blankets parted, letting in light, and then a massive red eye was blinking down at him. He raised his hands, ready to fight whatever monster was about to make his life hell, but a familiar voice broke him out of his preparations.
"It's about time you woke up."
"Kacchan," he said softly, his brain finally waking up and flooding with memories. "How long was I asleep?"
Katsuki moved, and then a wooden table was beside them, and Katsuki was holding his pocket open pointedly. Izuku was a little reluctant to leave his cozy little nest, but he stepped out all the same, finally feeling solid ground beneath his feet again.
"Oh," he squeaked, looking up at a crowd of excited faces. "Um, hi everyone! Wow you all look so big from here."
"Oh my god, you're so cute!" Ochako squealed, picking him up to stare at with her huge, round eyes. "You're like a little toy!"
Izuku blushed bright red, stumbling when Ochako handed him over to Tsuyu to take a look, Mina already hovering at the edges to wait her turn. He'd never understood the fascination girls seemed to have for small things, and he'd kind of just assumed that he'd never have to end up on the receiving end of it.
"Oi, cut it out," Katsuki growled. "He's still a damn human, you're gonna make him puke or some shit."
Izuku's chest was tight, his breathing shallow – he'd never spent so long in the air before, unless planes counted – but those had seatbelts. He needed solid ground, needed the world to stop swaying.
"For fuck's sake," Katsuki insisted, grabbing an offending wrist and squeezing until the grip loosened. "You lot are animals."
He set Izuku down carefully on the table, watching as he sat down in a hurry, taking a moment to remember how to breathe. When he looked up, there were looks of concern all around him, apologies already waiting on their lips.
"You didn't know, it's okay," he said quickly. "I'm still getting used to this. Everything is so big and so loud, it's gonna take a while, I'm sorry."
"Don't apologise to them, you shitty nerd," Katsuki huffed. "You're the size of a damn mouse, of course it's all weird."
Katsuki's voice was so soothing compared to the over-excitement of the girls, surprisingly soft considering his clear annoyance, and it took Izuku far too long to realise that the massive hand still rested on the table beside him.
"Thanks Kacchan," he said quietly, watching the familiar face lean in closer to hear him. "I'm glad you're here."
"Whatever, nerd," Katsuki huffed, his cheeks tinged with pink. "I guess I have to take care of your tiny ass, since these idiots are all so damn incompetent."
"I promise I won't cause any trouble," Izuku offered nervously. "I'd appreciate that, Kacchan."
"Whatever. I'm starving, you want a bite of my dinner or some shit?"
"Would you mind? It won't be much, I'm sure."
"Whatever. Come on, kitchen."
He stepped onto Katsuki's hand when it flipped over, grabbing at the thumb in a hurry to steady himself when it rose into the air. The trip was scary, but short, and next thing he knew he was on the kitchen counter, watching as Katsuki opened the fridge to search.
"I'm making salmon and salad," Katsuki informed him, an unspoken question hanging in his tone.
"That sounds yummy!" Izuku grinned. "Can I have a little?"
He sat down against the wall, leaning back to watch as Katsuki chopped and seasoned, throwing a generous chunk of fish into a frying pan before he went back to the vegetables. Every ingredient Katsuki cooked with always seemed so fresh, compared to the things Izuku bought – granted, he was usually buying bagged and boxed things from the convenience store, late at night when the prices were discounted.
"Where do you buy your vegetables?" he asked, watching red eyes dart up to glance at him. "They just look really nice, I mean. Fresh and colourful."
"Oh! That makes sense! I mean, I know the supermarket ones look pretty good too, but yours always seem a little bit nicer!"
"Cheaper too," Katsuki shrugged, looking away to avoid Izuku's eyes. "I'll take you."
"In your pocket?"
"When you're back to normal, asshole."
"Really? Yay! That would be great!"
Izuku teared up when Katsuki slid a little bowl toward him – it was usually one they would use for dipping sauces, he knew from the shape, but in front of him it still looked huge.
"Smallest one we had," Katsuki explained, blushing a little brighter. "Here, try this."
He snapped a toothpick in half and set it in the bowl, and Izuku couldn't help but giggle as he picked them up. They were still a little too big to use properly, but Katsuki had provided him a set of makeshift chopsticks, and the thought behind it alone made him smile.
Inside the little bowl, he found the tiniest salad in the world. His lettuce and cabbage were cut into crumbs, tomatoes and carrots and cheese in the smallest cubes in the world, and somehow Katsuki had managed to arrange it to actually look like a salad.
"It's amazing, Kacchan!"
He reached into his pocket out of habit more than anything else, surprised to find that when he hit the button on the side of his phone, it actually lit up. To Katsuki it must have looked like a pea in his hand, but it seemed fully functional and that alone made Izuku marvel.
He mumbled about it as he opened his camera, snapping photos of his tiny salad, and when he looked up he found an amused look waiting on Katsuki's face.
"What?" he asked, blushing. "It's so cute, Kacchan!"
"Whatever," he huffed. "It was kind of fun."
Katsuki shrugged, and Izuku's smile stretched wider, despite the happy tears still threatening to spill down his cheeks.
"Thank you, it made me really happy."
The massive hand reached out, and one thick finger poked him in the face lightly, squishing his little cheek.
"Stop fawning?" Izuku asked knowingly, smiling to himself. "I'll eat it. Thank you."
He set to work shovelling it into his mouth, watching as Katsuki did the same, leaning against the counter to take forkfuls of his much larger counterpart while he waited for the salmon to cook.
"Full yet?" Katsuki asked, when the tiny bowl was clean. "Want some fish?"
"Getting close," Izuku nodded, patting his stomach. "Fish would be nice!"
Katsuki tipped it from the pan onto his plate, beside the salad that still remained, and with the stove safely turned off he cut a sliver off the side of his chunk. It looked ridiculously tiny, next to Katsuki's piece, but when it landed in Izuku's bowl it looked perfect.
"It smells so good!" Izuku hummed, sniffing appreciatively. "Kacchan needs to cook for me more often!"
"Only if it's portions the size of my thumb," Katsuki snorted. "Takes no effort."
"I'll take what I can get!"
Izuku shrugged, smiling to himself still as he took a bite with his toothpicks, but when he tasted the salmon it made him moan loudly.
"So good!" he explained, when Katsuki looked up again. "Oh my gosh Kacchan, it's so good! I knew you were a good cook, but how did you make something so simple taste like the best thing in the world?"
Katsuki poked him again, and this time Izuku laughed, already tearing another bite of fish from his slice.
"Too much fawning, I know, but I'm serious! It's so good!"
Katsuki didn't bother to answer him out loud, but he reached for his knife, and Izuku watched with shining eyes as he carefully cut off another sliver. The tears finally sneaked their way out, when the slice landed on his plate, and Izuku sniffed hard as he wiped at his cheeks.
"Thank you so much, Kacchan!"
Katsuki held his phone up high above his head, staring up at the photo lighting up his screen. He wasn't sure why he'd taken it, honestly, but the smile splitting tiny, freckled cheeks was strangely addictive. He was weirdly proud of the miniature salad he'd managed to craft – it had actually been kind of fun to figure it out, and the nerd had been so damn excited by it.
He glanced over to his desk, where the pillow that smelled so much of Izuku's familiar scent lay, and where now Izuku slumbered under a fluffy blanket. It was usually a decorative item in Izuku's fanboy bedroom, decorated with All Might's creepy smile, and he'd been overly excited to actually use it for warmth. He'd crawled up onto his pillow, nestled himself in, and had been out like a light before Katsuki even lay down.
Katsuki had planned on just dumping him in his bedroom and coming back for him in the morning, but the nerves on Izuku's face had halted him in his tracks. He supposed it was fair, the world was huge for him, he could end up killing himself just by trying to get down from his bed. So Katsuki had found himself gathering bits and pieces from the nerd's collections, carting them down to his own room to set up a tiny bedroom atop his desk. The weirdest part had been the bathroom – he'd had to set the tiny idiot down on the toilet seat so he could pee from there, warning him not to fall in because there was no way Katsuki was gonna fish him out of his own piss.
"Morning Kacchan," Izuku yawned, his little green eyes blinking open. "Did you sleep okay?"
"Yeah," Katsuki nodded, finally sitting up and setting his phone aside. "You uh, okay?"
"Yeah! Oh, um, I need to... Use the bathroom, though. Again."
Katsuki picked him up in one hand, listening to him whine as the world was torn from beneath him but not bothering to answer the complaints about moving too fast. He set the nerd on the toilet seat just like he'd done the night prior, then turned away to brush his teeth, rolling his eyes when the whining began again.
"I'm not gonna be late to class because your dumb ass got turned into a damn teddy bear."
"Stop calling me a teddy bear!" Izuku huffed. "I'll only be a minute!"
Katsuki ignored him, returning to the toothbrush in his hand, and thankfully Izuku gave up arguing. After a moment Katsuki heard the tiniest sound of water falling, like a tap not quite turned off all the way, and then Izuku was sighing again.
"Kacchan, can I have a shower? I feel gross."
"How do you plan to do that, nerd? I'm not washing your ass."
"I can do it myself!" Izuku protested. "I was thinking maybe the sink? You could turn it on a little bit and I can shower under it?"
"I guess," Katsuki agreed, tossing his face cloth into the laundry hamper. "Let me give it a wipe."
He grabbed his cleaning supplies from under the sink, giving the basin a quick clean before he lifted Izuku over and set him in the bowl.
"Tell me when it's warm enough," he directed, turning the tap on to a steady little trickle. "And wash the piss off your hands while you're at it."
"I didn't pee on my hands!" Izuku objected, pouting. "You're so mean."
"Yeah, I'm so mean opening up my damn bedroom to you and carrying your ass around to keep you from being eaten by a stray dog or some shit."
"I still have my quirk! I could beat a dog!"
"No you couldn't, you'd be too busy fawning over how cute the giant puppy was."
He accepted all the same when Katsuki scratched off a little chunk of soap from the bar, offering it out on his fingertip. He gave his tiny hands a good scrub, then rinsed them off as the water warmed up.
"Maybe a tiny bit hotter?" he requested, watching Katsuki adjust the taps to suit. "Yeah! That's good! Um, you're not gonna watch me though, right?"
"God no, like I wanna see your pinprick of a dick. Wash your clothes too while you're there, though. They'll dry in like thirty seconds under a hair dryer."
"Okay! Thank you, Kacchan! I know I called you mean, but I really appreciate your help!"
"Whatever," he shrugged. "I'm gonna get dressed, don't drown."
He left a fresh washcloth on the side of the basin, hanging down low enough for Izuku to reach, then left the bathroom entirely to give them both some privacy. He was already dressed with his bag packed by the time Izuku called him back in, and Katsuki found him wrapped up in the face cloth, only his blushing face and sodden hair poking out from his little flannel cloak.
Katsuki turned off the tap and pulled his hair dryer from under the sink, but paused again when he glanced at Izuku's red cheeks.
"This is probably gonna be loud," he pointed out. "You wanna go back to the desk while I do it?"
"O-Oh. Um, y-yeah, if it's okay."
He set the dryer on the edge of the sink, picking Izuku up instead and making sure his cloth remained wrapped around him securely. Izuku mumbled another thank you when Katsuki set him down in the next room, looking oddly ashamed of himself as he sat on the desk to wait, but Katsuki decided against addressing it just yet.
Back in the bathroom, he dried the tiny clothes carefully, making sure there were no damp spots left behind since he was sure the nerd would be too awkward to tell him. He wasn't even sure why he was making such an effort, to be honest – any of the idiot's friends could have been the one to take care of him, there was no real reason for it to be Katsuki. Surely their perfectionist class president could have handled the job adequately, kept the tiny nerd from killing himself. Maybe even the halfie bastard, he was admittedly pretty good at remaining calm and thinking about his actions. Katsuki and Izuku had been together for so long, though – it had somehow felt natural for him to be the one who took Izuku in, who protected him from idiots with no sense of volume or relative strength
"Here," he said softly, setting the warm, dry clothes on the desk beside Izuku's feet. "Put 'em on and we'll go to class."
"Thank you for all your help, Kacchan. I'm sorry to be such a bother."
"It's fine," Katsuki shrugged, turning away to let the nerd get dressed in private. "I said I would do it, no one is forcing me."
"I know," Izuku giggled. "I appreciate it though!"
When the pair were both ready, Katsuki held his blazer pocket open, letting Izuku climb inside and get comfortable. The night prior, he'd tucked himself away in the darkness where they wouldn't be asked a thousand questions on the train, but this time he kept his head out to watch. The world looked so different from his position, everything so big and intimidating, but in Katsuki's pocket he somehow felt safe.
"Kacchan, he's open on his left! See look he braces his right arm when he attacks, and it leaves his left wide open! If you move quickly and use your explosion to change course you should be able to duck under his attack and-"
"Will you shut the hell up?!" Katsuki demanded, dodging to the left and slamming a fist into the villain's ribcage all the same. "You're so damn annoying!"
"But Kacchan I can't fight, I've gotta at least help with strategy!"
"Keep it to your damn self, I don't need your help!"
Katsuki threw his arms up, blasting the second villain as he tried to rain down arrows, and immediately Izuku was mumbling again.
"If you can stay close to the arrow guy, they'll both be at a disadvantage, Kacchan. He wants to keep you at a distance so he can fire at you before you hit him back, and the other guy wants you in close quarters to fight hand to hand, so they don't want to get close to each other and ruin each other's attacks."
"I know that, you dumbass!"
His sentence was cut off quickly when Katsuki whirled around, Izuku's little hands losing their grip on Katsuki's thick belt. He squawked as he slipped out from under the fabric, firing away from the safety and comfort of Katsuki's body heat, activating his quirk and bracing for impact.
The crack of Katsuki's explosions rang through his ears, and Izuku hit something solid, surrounded by a wet heat.
"Hold on tight, you dumb nerd."
He turned his head to see an arm attached to the humid grip, his childhood friend scowling at the other end. The villain moved to throw another punch, his first one foiled despite Katsuki's distraction, and Katsuki shrouded Izuku with his hand. A loud explosion rattled the concrete around them, and Izuku peeked out from between Katsuki's fingers just in time to watch both villains go flying, hitting the ground and not moving.
"You caught me," he said softly, when Katsuki's grip loosened a little. "Kacchan..."
"Like I was gonna let you break all your damn bones again on my watch."
"Kacchan is amazing."
"Shut up, idiot," Katsuki grumbled. "Thankfully they didn't notice the stupid Deku plushie go flying across the street."
"Not a plushie," Izuku protested half-heartedly, holding on tight when Katsuki hooked him through his belt again, an empty grenade at his side. "Thanks for catching me."
"Whatever. Told you I'd watch out for you."
Izuku nodded, contemplating his next words carefully, but a loud siren cut him off before he could quite form them.
"Good work today," one of the sidekicks called out, some extra from their intern agency that Katsuki hadn't bothered to learn the name of. "You're dismissed, we'll see you tomorrow!"
Izuku held on tight as they returned to the agency down the street with a wave of other sidekicks and interns, averting his eyes when people began to undress. He sat back on the benches to wait, mumbling to himself in quiet contemplation, but when a hot weight hit him in the face he yelped.
"Kacchan!" he complained, throwing the sweaty shirt aside with a pout. "Look where you're throwing!"
"I did," Katsuki countered, smirking. "Shut your damn trap."
Izuku folded his arms, huffing, but when Katsuki bent over to shed his pants, his sulking was quickly forgotten. Katsuki had gained a couple of scars during their school years – nothing as bad as Izuku's, not even close, but it was kind of fascinating to eye them up all the same. The worst one drew a trail from his back down across his side, as if it were pointing at the defined ab muscles, telling him "look over here while you have the chance."
Izuku was pretty sure school would be ten times easier if he didn't have such a massive crush on his old friend.
"Kacchan, what happens if I never go back to normal?" he asked quietly, when Katsuki tucked him back into a blazer pocket to return to campus. "What if I'm stuck being tiny forever?"
"Then we'll have to buy some smaller forks."
Despite himself, Izuku couldn't help but laugh, and he saw a little smile twist at Katsuki's lips too.
"I'll get them to put a chest pocket on my costume. With a seatbelt or some shit."
"You know what I mean, Kacchan."
"You always said you'd be my sidekick, right? Maybe this is your chance to make your dream come true."
"My dream is to be a hero."
"And you might actually succeed, if you're tagging along with my victories."
Izuku fell silent, huddling into the pocket a little more, but when the group dispersed he felt a weight land on his head. He looked up to see Katsuki's smallest finger, ruffling his hair gently, and his frown softened a little at the affectionate gesture.
"I'll take care of you," Katsuki assured him. "We'll go shopping for doll clothes together."
Izuku couldn't help but laugh at that, especially when the fingertip moved to poke his cheek lightly.
Izuku stayed quiet through their debriefing with the management staff, only speaking up if someone asked him a question directly, and as much as Katsuki had thought he'd enjoy the peace and quiet, it just seemed weird. Thankfully he seemed to perk up a little as they walked back to the dorms, answering sufficiently when Katsuki spoke to him, and his little stomach growled when Katsuki mentioned food.
"Sorry," he squeaked. "I can make something, it's okay."
"I'll cook, it's whatever."
The dorm was empty and quiet, half their classmates away at various agencies for work experience still while the other half sat in dull school classes. Katsuki walked up to the kitchen counter and held his pocket open, letting Izuku climb out on his own steam, then turned to the pantry while Izuku got comfy. He started pulling out bags and jars, setting them out on the bench, and Izuku just watched in silence as he measured and sifted and whisked.
Katsuki fired up the stove, melting butter in the pan for lubrication, and he cracked a smile when Izuku finally spoke up from behind him.
"Are we having pancakes?!" he asked, practically buzzing in his excitement. "I haven't had pancakes in so long!"
"Felt like sugar and carbs," he shrugged, dripping a teaspoon of liquid onto the hot surface and watching it sizzle. "Just don't tell the shitheads in class or they'll nag me to make them for them too. At least yours aren't hard right now."
He waited a moment for them to bubble, then flipped them carefully with his spatula, pleased to see they came out neat and clean, perfect circles, without deforming or splitting when they flipped. He took a little plate from one of the cupboards, stacking the pancakes with the utmost care – he wished he had a pair of tweezers on hand to help, the spatula was really far too big for such a delicate task – then with pride he slid the plate across the bench, turning around to see the delight he knew would be on Izuku's face.
Instead, he nearly knocked the plate off the counter.
"H-Hi, Kacchan," Izuku stumbled, smiling sheepishly as he covered himself with a tea towel. "I, um- I'm just gonna go get some clothes first."
For a moment they just stared at each other, then Katsuki looked down at his tiny pancake stack.
"I think I'm gonna need a bigger plate."
Izuku laughed brightly, shiny eyes squinting a little, and Katsuki's heart thumped a little quicker.
"It's so cute!" Izuku praised, back to his normal self suddenly despite his awkward nakedness. "Was the salad this cute too?! They looked mostly normal to me! Wow, look at it! Oh my gosh!"
"Shut up," Katsuki blushed, tearing his eyes away from Izuku's nude muscles. "Go put some damn clothes on."
"Yeah," Izuku laughed again. "Um, thank you. For all your help."
"Whatever. It's fine."
Izuku leaned over his shoulder, stabbing the tiny pancakes with a fork and stuffing them in his mouth, and Katsuki huffed when he hummed contentedly.
"Tasty, I knew they would be. Kacchan is such a good cook. Thanks for lunch!"
He turned to leave, and Katsuki blushed brighter when he caught a glimpse of bare ass, taking a second to compose himself.
"Oi, Deku," he called.
"Hm? Yeah, Kacchan?"
"Come back when you're dressed," he instructed, his voice awkward despite the confidence he feigned. "I'll cook you a proper one."
"Really? Thanks, Kacchan!"
In a moment of boldness, Izuku leaned over again, pressing a tiny kiss to Katsuki's cheek.
"I'll be right back," he giggled, when Katsuki spluttered and popped off tiny explosions. "Can I have chocolate chips on mine?"
Izuku walked away, still smiling widely even though his heart was pounding, and Katsuki stared at his bowl of pancake batter.
"Stupid nerd," he muttered, cheeks still burning as he snatched a bag of chocolate chips from the cupboard and started a new pancake. "Embarrassing dumbass, what the hell was that shit?"
He took a handful of chocolate chips, sprinkling them on the slowly cooking batter as he muttered, his cheek extra warm where Izuku's lips had touched it.
And if his pancake happened to be shaped like a heart, no one ever had to know.