Chapter Text
Izuku would consider himself highly unprepared to handle any kind of pest in his dorm room.
Waking up in the middle of the night to the sound of books toppling off of his bookshelf had been alarming, especially since he couldn’t locate the source of the noise at first. Once his eyes landed on the pile of books across the room, he immediately tensed, clutching his blanket embarrassingly tightly as his gaze scanned for the culprit behind the mishap.
He wasn’t shocked to know that there were mice in the school— the amount of times he and his classmates’ things had gone missing was too many to count. Bits of food had vanished from the kitchen time and time again, and while some students offered the idea that maybe there are ghosts in the school! it was simply common knowledge that UA had a mice infestation.
Izuku’s gaze danced over the bookshelf, and when he caught the slightest bit of movement on one of the lower shelves he tensed. There really was a mouse in his room.
Swallowing, he wracked his mind for a solution. He had never dealt with a mouse before, and while a small part of him wanted to go back to sleep and ignore it, he felt a sudden sense of responsibility to do something. The mouse was in his room, after all.
Another minute passed before Izuku tentatively pushed his blanket off of him and lowered his feet to the cold floor. After a moment's hesitation he straightened up, subconsciously holding his stomach as he crept forward towards the bookshelf.
The walls were barren on either side of the shelf, which meant if the mouse tried to run, Izuku would see it. The green-haired boy stopped a few feet away from the bookshelf, lowering himself into a kneel.
He sat back on his heels, holding his breath as to not alert the critter to his presence. He didn’t know exactly what to do— he was not planning to kill an innocent mouse, so transferring it outside seemed to be his only option. Would it be possible for him to grab it with his bare hands? He could handle a bite or two, he had dealt worse injuries before.
He nodded to himself. All he had to do was locate the mouse, grab it quickly, and carry it downstairs and into the courtyard. He wished he had a spare box or cup to contain it, but his small dorm room lacked either of those.
Izuku cautiously pushed the books that had fallen aside. There was a significant gap of empty space on the second shelf, where the books had clearly fallen from. Was the mouse hiding there somewhere?
His green eyes locked on a shadow. Something small was hidden in the space behind the shelved books.
He relaxed slightly, comforted to know precisely where the mouse was. Exhaling softly, he reached forward with both hands.
His left hand closed around one of the books, while his right hand hovered nearby. All he needed to do was whip the book away and snatch the mouse up while it was startled. While Izuku didn’t necessarily want to frighten the mouse, he knew it would be inevitable, and he set his plan into action.
With a yank of his arm he tore the book away. His right hand dashed forward to close around a small, warm shape, which immediately began fighting in his grasp.
Izuku stiffened, muscles locking into place. Whatever he had found on the shelf was definitely not a mouse.
“Damnit, put me down, you idiot— I’ll kill you—!”
The violent words were harsh, but Izuku could see the panic in the eyes of the tiny human he had trapped in his fist. Miniscule hands he wouldn’t even think to be possible punched and shoved against his fingers, barely even making a dent. “Let me go, damnit!”
“I— what are you?” The words tumbled out of Izuku’s mouth before he could think. He dropped the book in his left hand, bringing the tiny person forward to see him better.
The surprisingly broad shoulders were still tiny to Izuku, fitting easily underneath his fingers despite how much the tiny human was lashing out. The spiky blonde hair matched his aggressive, violent behavior, as well as his furious eyes. Mesmerized, Izuku touched the pad of his finger to the tiny human’s hair, completely fascinated.
“Don’t— don’t touch me!” The human snarled.
Izuku’s eyes met tiny, fiery ones, and he suddenly blanched.
“Wait, oh my god, I’m so sorry, I didn’t mean— I’m sorry—“ he thrusted his hand forward to haphazardly drop the tiny person onto the bookshelf, cheeks flushing with embarrassment. How could he treat a person like that?
The tiny human immediately scrambled to his feet, backing away while eyeing Izuku with the angriest pair of eyes he had ever seen. Izuku’s stomach twisted with guilt, and he lowered his hands to his lap. He should have been more careful with his actions before he overstepped his boundaries and manhandled the little guy. Not a very good first impression.
“I’m sorry,” Izuku forced out, fiddling his thumbs together. He could still feel the tiny body in his grasp. “I— I wasn’t really thinking. Did I hurt you?”
The tiny human scoffed, pressed against the shelf behind him. “It’ll take more than that to hurt me, dumbass.”
Izuku supposed he should be grateful the tiny guy was responding with anger and not complete fear. He could deal with people being mad at him.
“I, um— that’s good, I’m glad you’re okay.” Izuku took a deep breath, his mind still racing with questions. Did somebody in this school have a shrinking quirk he didn’t know about? He didn’t recognize this person at all. “Once again, I’m sorry. I shouldn't have picked you up like that.”
“Damn right,” the tiny snapped.
“Sorry.” Izuku gave a hum, unsure of how to respond. His fingers drummed over his knee. “If you don’t mind me asking, uh— who are you?”
The tiny human curled his lip, but didn’t lash out with anger as quickly as Izuku thought he would. The blonde seemed to actually consider his question for a moment before growling, “why do you want to know?”
“Well…” Izuku scrunched his nose. “I mean, you’re in my room. I kinda think I should know.”
“I don’t owe you anything,” came the fiery response.
Izuku exhaled, giving the small man a pleading look. “I’m just curious. Is your size part of your quirk? Are you a student?”
The tiny huffed, glancing to the side. “Screw off.”
That wasn’t the answer Izuku wanted. The green-haired boy shifted on his knees, noticing absentmindedly how the tiny man’s gaze zeroed in on his movements. Did he still think Izuku was going to grab him? That didn’t sit well with Izuku.
The human’s gaze lowered to the floor, landing on the pile of books, and he tilted his head. “Can you at least tell me why you knocked my books over?” Izuku pleaded.
The blonde’s face went blank for a moment before, to Izuku’s shock, he burst into laughter. “You think I did that on purpose?” He jeered, making Izuku blink. “Obviously that was an accident. Sorry for disturbing your slumber, giant.”
“Oh.” Izuku probably should have guessed that.
The tiny blonde ran his hand through his hair for a moment. “Speaking of that, leave me alone.”
“What?”
“You’re not supposed to be talking to me,” the tiny human said with a growl. “It’s against the rules.”
“Rules? Wait, what rules?” Izuku’s panic skyrocketed.
The tiny human dismissively waved a hand. “Stop asking questions. Go to sleep so I can leave. And don’t tell anyone we met.”
Izuku bit his lip, resisting the urge to interrogate the tiny human any further. Did he live here? Did the teachers know about him?
After a second of consideration he leaned back. “...okay.” He supposed he owed the tiny human confidentiality after grabbing him earlier. Stomach fluttering with regret, he dared to ask a final question. “Will I see you again?”
The blonde scoffed. “Maybe, if you don’t grab me again. Now screw off.”
Izuku’s shoulders slumped with relief. Satisfied with that answer, he pressed his hands to the floor and prepared to stand. “I’m Izuku Midoriya, by the way.”
“I didn’t ask,” the tiny human grumbled. After a beat of silence, however, he muttered, “I’m Katsuki Bakugo.”
Izuku smiled. He glanced over Katsuki’s small form one final time before pushing himself to his feet and taking a step back.
From this height, Bakugo was positively miniscule. The blonde crossed his broad arms, glowering up at the taller of the two, clearly impatiently waiting for him to avert his attention.
“Um… goodnight, Katsuki,” Izuku said.
Katsuki yawned but gave no other response. Amused and fascinated, Izuku turned away and crossed the room to his bed.
As he laid down, purposely keeping his gaze on the ceiling and not the bookshelf, he couldn’t help but smile again.
There was so much he didn’t understand about this strange interaction. If there was one thing he was certain about, it was that he could not wait to see Katsuki Bakugo again.