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“Kirishima watch out!” Sero gave a shout as one of the villains they were currently trying to fend off shot out with their quirk when the redhead had his back turned to them.
Kirishima and Sero had been out together doing a food run for everyone when they had been attacked by random villains. Kirishima was trying to get the taller of them subdued when the shout from Sero came. He turned at the last second, but wasn’t quick enough to get out of the way of the shot of green light that came at him. It hit him directly in the chest and knocked the wind right out of him as it sent him flying to the ground.
When he was able to breathe properly again, he saw the villains who had attacked them running off. Apparently they had done what they’d come to do. Sero ran over to him and bent over to help him stand up, a worried look on his face.
“Are you okay?” He asked checking him over. “That looked like it really hurt.”
Kirishima took a moment to gather his wits about him before he gave a slight nod. “Yeah,” he started to say. “Yeah I’m okay. It stunned me more than anything.”
Sero stepped away from him after he saw he could stand on his own without any help. He kept watching him a moment before seeming to be satisfied.
“What the hell was that though?” He said after they’d picked up their things that weren’t ruined completely.
“Some kind of stunning quirk I think.” Kirishima said as they finally started heading back.
By the time they got back to the dorms, everyone had apparently started getting worried. And when they found out that Kirishima had been hit by some of kind quirk spell, they fretted even more. Mostly Ashido and Uraraka did that though. Which he was grateful for, but found completely unnecessary.
“I’ll be okay guys.” The redhead stated with a grin for them all. “I’m kinda tired after all that though, I’m gonna head to bed early.”
As he walked away from the common area in the dorms, he could hear Ashido giving Sero a hard time. He ignored it for now and figured come morning he would talk to her and clear things up with her. It wasn’t Sero’s fault that Kirishima had been hit by the villains quirk. Kirishima just simply wasn’t as vigilant as he should have been.
Getting ready for bed he had to admit to himself that he felt pretty wiped out from their little adventure today. His body felt exhausted, so despite having a couple questions left for an assignment, he figured he would finish them on his lunch break before the class started.
Once morning came around, he didn’t feel nearly as tired as he had the night before so he figured he was okay. That the sleep he got had brought him back to normal. It was only after he’d gone through his regular routine of getting ready in the morning that he noticed anything was off.
He had been in the middle of spiking up his hair when he felt a pain in his chest in the same exact spot he’d been hit with the green light the previous day. He clutched at the spot, eyes going wide as he started to panic.
What was wrong with him? What was going on? He was only a teenager. Should he really be getting pains like this in his chest? He caught sight of himself in the bathroom mirror and saw his face and body start to change.
Slowly as he continued to change he lost sight of the mirror entirely. Was he… shrinking?! What the hell was going on? His panic didn’t subside as he realized this, it got worse. Why was he shrinking?! Why the hell was this happening to him?!
Not only was he shrinking, but so was his clothing! In his panicked state, Kirishima did the only thing he could think of. He ran out of his room in the dorms and made a mad dash for the stairs. He didn’t have the patience right now to wait on the elevator. He needed to see Aizawa right that very second. He would know what to do. He had to.
Not paying attention to anything around him once he left the dorm building 1A was residing in, he didn’t realize that almost half the class was already heading to the school building and saw him. Well, they saw a little red blur go passed them more than anything.
“What...was...that?” Uraraka asked blinking in surprise.
“I have no idea.” Midoriya said. “Whatever it was, I think it came out of the dorms.”
They all agreed it was weird, but soon fell onto new topics of conversation as they headed to homeroom.
Once Kirishima got into the school building, his first thought was to go to the teachers lounge to look for Aizawa. On his way there though, he saw Present Mic and All Might. Making a b-line for them, he called out to get their attention. Waving his now little arms around to catch their attention easier.
“Can I help you young man?” This was from All Might. “Aren’t you a little young to be in the high school?”
“It’s me! Kirishima!” He said with a huff. “I don’t know what’s going on! I woke up this morning normal and while getting ready for classes I started changing and now I’m like this!”
“You just randomly started getting smaller?” Present Mic said and bent down to be more level with kirishima’s now much shorter stature.
“Yes!” He said, but then remembered the night before. “I was out with Sero last night getting snacks and stuff for our movie night we were supposed to have but we got attacked by some villains. One hit me with this kind of light and now I’m like this!”
“I think we should take him to Recovery Girl.” All Might suggested as Present Mic stood up holding a baby sized Kirishima in his arms.
“Take who to Recovery Girl?” A tired voice said from behind them.
Turning around they all came face to face with Aizawa.
“Sho-“ Present Mic started but cleared his throat to correct himself of the slip-up. “Aizawa! We think we need to take Kirishima here to Recovery Girl. He’s clearly not himself right now.”
“That’s Kirishima?” He asked looking at the small redhead.
Kirishima nodded his head a couple times before trying to launch back into his story of what happened. Aizawa held up a hand to stop him. “Go see her and get to class soon as she’s done with you.” Was all he said before starting back on his way to 1A’s homeroom class.
“Yes, Mr. Aizawa.” He said in a much higher pitched voice than he usually had. He looked up at Present Mic who still had him in his arms, then to All Might. “Are you going to come with me Sir?”
“We can if you’d like us to.” All Might replied with a smile for him. “Emotional support if you want it.”
Kirishima did want it. He was worried something was really wrong with him. He’d felt off since he’d been hit with the villains quirk the night before, but now that he had not only shrunk in size, but his voice had reverted back to that of a child’s… what did this mean for him as a student in UA?
Eventually they made it to the nurses office and sat him down on the chair by Recovery Girl’s desk so she could take a look. Hopefully she would be able to determine what could be done to fix this for Kirishima.
“What do we have here?” She said coming into the office from what they assumed was the bathroom attached to her office.
“Young Kirishima here is clearly not himself.” All Might provided.
“I got hit last night with a quirk and wound up like this this morning while getting ready for school.” Kirishima said giving her the short version.
After a few questions from Recovery Girl, Kirishima was told that as he wasn’t injured in any way, there was very little that she could do. She had seen similar cases like this before and told him that he should go back to normal within a few days time. After that, she sent him on his way.
“Sorry young Kirishima.” All Might said scratching at the back of his neck. “We thought she would be able to tell us more than that.”
“It’s okay All Might.” Kirishima said in a rather dejected tone. “At least it isn’t life threatening like I had thought.”
“If anything changes though,” Present Mic cut in, “you go see her again and tell her what’s going on.”
“I will.” He replied and headed toward his homeroom class.
Had he been his normal size, Kirishima would have made it to class within a couple of minutes. But since he was pretty much the size of a baby, it took him quite a bit longer to get there. And when he did make it to class and was trying to slide the door closed, the whole class went dead silent.
All eyes had turned to look at him as he made his way to his desk behind Kaminari. He managed to get the chair pushed out, but getting up into it was a different story. He had barely managed to get one of his legs up onto it when a loud explosion type of sound went off. It startled him to the point that he lost his hold and went tumbling to the ground causing everyone to gasp loudly and reach out to try and help no matter how far they were.
He would have hit the ground had Tsu not acted when she did and wrapped her tongue around him so he didn’t hurt himself. Eyes wide like saucers, he looked at her.
“Thank you Tsu.” He said and apparently the sound of him speaking like that was enough to set off another loud booming sound.
The whole class, including Aizawa and Kirishima himself turned their attention to the other side of the room to the only likely culprit: Bakugo.
The blonde got up from his desk and made his way to where Kirishima was and taking him from Tsu’s hold, carried him to his own desk.
Everyone had remained silent after that initial gasp when Tsu had caught him. They still stayed quiet as they watched Bakugo carry a baby sized Kirishima to his desk and set him down facing the blonde.
Reaching over, Bakugo took the redhead’s cheeks between his hands and started squishing them. A blush spread across the blonde’s cheeks and an even louder boom exploded out from his hands when he moved them away from Kirishima. Though he was the size of a baby he still had full control of his quirk so he hardened his body to protect himself from the flames. His uniform jacket wasn’t so lucky to survive though.
No one had any idea as to what to do. Was Bakugo being...cute? This was not something they were equipped to handle. They all turned with equally shocked and terrified expressions on their faces to Aizawa. Surely he would know what to do.
“As I was saying…” the teacher started saying almost as if nothing happened, only to have the bell ring signalling the end of homeroom.
As if they were all scared of what Bakugo would do next, they all jumped from their seats while grabbing their things and running from the room. Bakugo was much slower leaving the room. He picked up his bag and lifted Kirishima into his arms.
“Uhm Bakugo?” Kirishima started to say as he was carried. “Why are you carrying me? I can walk to Present Mic’s class.”
“You’ll get trampled on by everyone.” The blonde retorted. “Don’t need you getting fucking hurt cause of these assholes.”
Kirishima blushed at that and kept quiet the rest of the way to Present Mic’s class. Once they got close to his classroom they could hear their classmates yelling over one another trying to get the teacher's attention. It was obvious from their tones that it was about Kirishima and what happened with Bakugo in homeroom.
They quieted down as Bakugo walked in with Kirishima in his arms, still unsure as to how to deal with this new development.
“What do you want assholes?” He demanded with a glare for them all as he sat Kirishima down in top of his own desk before sitting down himself.
“You see Sir?” Kaminari, the brave one of them all apparently, said. “He’s being normal for once! It’s scaring everyone.”
Bakugo at this point had tuned them all out and was focusing his attention on Kirishima. He was playing with his fingers, trying to see how much bigger his own were compared to the redhead's now. And just like in homeroom, little explosions would set off at random.
“It’s a fairly simple explanation really.” Present Mic started to say with an amused tone as a blush crept across Bakugo’s face yet again.
“It is?” Sero asked, but was interrupted by another “boom” going off. “Because it doesn’t seem like there is one Sir. Not for Bakugo acting like this.”
“For starters were going to ignore Bakugo’s explosions as best we can.” Present Mic said.
“But how can we when they keep going off every two seconds?!” Ashido asked with a pout.
“Shut the hell up Pinky!” Bakugo yelled. “They are not.”
“Bakugo,” Kirishima tried to cut in to calm the blonde down a little when another explosion went off.
“We do our best to ignore them Ashido.” Present Mic began again. “Bakugo’s body is going through an overload of happiness right now. And because of it, his body and mind don’t know how to handle it. So to help him deal, his quirk keeps going off.”
“An overload of happiness?” A few of the students asked, clearly confused by this.
“Yep. Studies have shown that you’re more likely to pop bubble wrap when you see cute animal pictures. This is basically the same thing. Here. Let me show you.” The teacher turned to Bakugo and asked, “Bakugo what do you want to do right now?”
“PUNCH HIM IN HIS SQUISHY LITTLE FACE!” He said rather loudly right before another explosion went off again.
“See?” Present Mic said rather excitedly.
“Is there a name for… whatever this is?” Midoriya asked pushing his desk back a bit as he was directly behind the exploding blonde.
“There is actually!” Came the reply with a grin. “It’s what is referred to as ‘Cute Aggression’ and can happen at any time.”
The rest of the class was spent asking Present Mic different questions about what brought people to realize that this was actually a thing.
Kirishima, though usually tried his best to keep focused in all of his classes, paid little attention to any lectures that day. Bakugo had kept him placed on his desk and continuously squished his cheeks while explosions went off.
When lunch time came and they grabbed their food, Bakugo had a normal sized meal, whereas they got a very small amount for Kirishima. He was much smaller than he normally was so he couldn’t eat as much. Despite the protests that the redhead was throwing out, Bakugo stood firm and kept the amount to a manageable size.
“Kirishima,” Kaminari said. “You may as well give up bro. You know he won’t budge once he’s made up his mind about something. He tried blowing up Ashido for suggesting she hold you while Bakugo got both of your lunches after all.”
“I can’t really blame Bakugo though to be honest.” The pink haired female said and leaned across the table to gently pinch Kirishima's cheeks. “You’re just too cute to handle like this Kiri.”
“Leave him the fuck alone Pinky!” Bakugo snarled our around his mouthful of food.
Kirishima watched them like it was a tennis match, his head swiveling from one to the other. Eventually he finished his own portion of food and came to realize that Bakugo had forgotten to get them something to drink to go along with their meals. Thinking it would be a good way to say thank you to the blonde for making sure he didn’t get trampled in the halls between classes, he climbed down from the table, to the chair and then hopped down to the ground.
Most everyone had turned around to get a look at him, wondering what had happened. But most were in the same boat as Bakugo: they wanted to squish those cheeks and snuggle the tiny redhead to bits.
He made his way to the area they kept the juice boxes and found his first dilemma. How was he going to get up there to grab the one he wanted? He decided he needed to try and reach up for the juicebox. He needed to get that drink for Bakugo as thanks.
Yaoyorozu was just getting to where the drinks were held and saw Kirishima jumping to try and get a hold of the edge of the counter to be able to somehow pull himself up enough to grab hold of a juicebox.
“Do you need help Kirishima?” She asked looking down at him when he stopped his jumping and stood there looking up with his hands on his hips and a pout on his lips.
“Can you grab me a juice box for Bakugo?” He asked looking up at her with an adorable little smile.
“Of course!” She said. Blushing all the while at how cute he looked. “What one would you like?”
“The wild cherry one if they have it.” Kirishima said.
Grabbing the box, Yaoyorozu gave him a smile. “Here you go.” She said. “It’s the last one too.”
“Thank you Yaoyorozu!” He said and clutched the juice box to his chest as best he could since it was so much bigger than he had anticipated.
Watching him walk back to his table Yaoyorozu couldn’t help but make a whimper like sound in the back of her throat. She felt like she was going to combust from cuteness overload watching him waddle to the table. The box was clearly heavier than he had thought it was going to be, and much bigger.
“Too cute.” She said to herself before grabbing her own drink and rushing to the table Jiro was sitting at waiting for her.
At his own table, Kirishima noticed that no one had realized that he had snuck off. They were still arguing over who should keep him safe between classes and who should have him during their classes. It was all pretty ridiculous to him if he was being honest. Didn’t they know who he would choose to keep him safe from getting trampled and during classes?
With a huff, Kirishima did his best to slide the juice box onto the chair and then proceeded to climb back up the way he’d gotten down. Once he was back on the table, he picked the juicebox back up and waddled his way over to Bakugo.
“Here you go!” he said with a wide smile for the blonde as he set the box down onto his lunch tray.
“The fuck is this for?” Bakugo asked picking it up and looking at the redhead.
“A juicebox to say thank you for helping me out!” he said with a smile that kept getting wider and wider.
Looking at Bakugo, Kirishima and the other three at the table could see his face getting redder by the second and knew that an explosion was coming. Kaminari, Ashido and Sero all pushed their chairs away from the blonde as far as they could given everyone around them at other tables, while Kirishima eyed him warily and wondered if he should activate his own quirk to protect himself from the impending blast.
“Get out of the way!” Kaminari yelled suddenly, “He’s gonna blow!” Not even two seconds later, Bakugo let out an explosion much bigger than any of the others he’d let off in class.
At the very last second, Kirishima was able to activate his quirk, saving himself from being set ablaze, but his school shirt that had managed to survive the second explosion from earlier, wasn’t so lucky this time.
“Dude!” Kaminari said, eyes huge. “All that over a juice box?!”
Bakugo stood up from his chair rather abruptly and grabbed the box of juice and Kirishima into his arms before storming off yelling at Kaminari to, “shut the fuck up already!”
Over the next couple of days, things didn’t get any easier on Bakugo and his random explosions during classes or lunch breaks. He refused to let anyone but himself take care of Kirishima. That included holding him while they walked to their next class, went to the training grounds, to the cafeteria or even to the dorms. It also included keeping him safe during the night.
Logically speaking, Bakugo knew that Kirishima could take care of himself. He wasn’t an invalid. He just needed to make sure that he was safe. Especially at night when he could roll out of bed and really hurt himself. And since he was too small to reach the handle on his dormitory room door, he wouldn’t be able to leave if he were to need to use the bathroom.
No. Bakugo needed to protect and take care of him at all times. Day or night. He couldn’t trust anyone with the redhead’s safety. No one as good enough to do it except for himself.
It was at the end of the third day and Bakugo was just getting out of the bathroom stall from doing his business when he saw probably the cutest thing he thought he would ever see. Mini Kirishima was sitting on the bathroom sink counter where he had been left by the blonde. He was facing the large mirror with his now too big toothbrush and toothpaste in his hands and his face was covered in toothpaste.
Bakugo stood frozen in place for a good few minutes just staring at the sight in front of him. His face was getting redder and redder the longer he stared at Kirishima in his current state. He could feel the pressure building up inside of his body, an abnormally large explosion building as his hands started sweating more and more.
“Hi!” Kirishima grinned at him with an adorable smile that split his face in two almost. There was no response other than the bathroom being destroyed by the explosion.
By the afternoon of the fifth day, Aizawa had had enough of the explosions. Recovery Girl hadn’t had any progress on finding a way to change the redhead back to normal with her quirk. Aizawa was getting really tired of the explosions interrupting his lectures. Not to mention the fact that Kirishima was sitting on Bakugo’s desk and everything was distracting the boy.
“Alright,” Aizawa said clearly annoyed as Bakugo placed a headband with black kitty ears onto Kirishima’s head that Yaoyorozu had created causing another explosion to go off again. It was the fifth on that class. “Kirishima you’re coming up front with me. I’m tired of the explosions and you not paying attention.”
He stepped around the podium he was behind and headed over to the blonde’s desk. He picked Kirishima up and went back. He placed him on the podium facing the rest of the class and kept his eyes on the blonde, his hair going up as he activated his quirk to stop Bakugo’s from going off.
The longer that Aizawa had his gaze focused on Bakugo, the more Kirishima noticed that he was starting to look a little worse for wear. His face was getting pale and shiny from sweat, his breathing looked erratic from his perch up on the podium and he was shaking. Kirishima didn’t think that stopping Bakugo from using his quirk was a good idea. He looked like he was deathly ill.
“Aizawa Sir?” Kirishima said tugging on the sleeve of the teacher's shirt.
“What Kirishima?” he said not looking at him.
“I think you stopping Bakugo’s explosions isn’t a good idea.” Kirishima commented. “He looks really sick now. I think you should stop erasing his quirk Sir. Present Mic said it’s how his body is dealing with me being like this.”
“Always such a bother.” the man sighed heavily. “Everyone out of your seats and into the hallway. I don’t feel like bringing any of you to the nurses office.”
It didn’t take them all long to push their chairs back and make a mad dash for the hallway. None of them wanted to get blown up by Bakugo’s explosions.
“Kirishima, that goes for you too.” Aizawa said as he placed the small boy onto the floor.
“No,” he said and ran toward the blonde’s desk. “He’s been helping me stay safe while I’m like this. It’s only fair that I help him through this. It’s the manly thing to do!”
“Bakugo I’m going to let my hold on your quirk go.” Aizawa said as he kept his gaze on the blonde while placing the redhead onto the ground. “Do you think you can keep the explosion off until I get out of the classroom?”
Aizawa knew he should try and get the blonde to one of the many training grounds, but from the looks of him, he doubted he could even make it to the classroom door. At Bakugo’s jerky nod Aizawa blinked, giving the boy his quirk back. He ran for the door and yelled for the students to run down the hall and away from the classroom.
It wasn’t even seconds later that a deafening boom sounded as the loudest of all of the explosions engulfed the entire classroom and spilled out into the hallway. The explosion had caused all the classes to spill out into the hallway, all of them wanting to know what had happened.
The explosion was so big that two days later, they were still using a spare classroom for their homeroom. Bakugo had caused more damage to the room than they had originally thought it had. It had also been a week to the day that Kirishima had been shrunk to the size of a baby.
They were all sitting in their seats, all early for a change, and Kirishima was on Bakugo’s desk playing with the blonde’s hair. It still weirded them all out that Bakugo allowed the redhead to do things like that to him. The blonde had his hands on Kirishima’s waist to make sure he didn’t fall while he stood on the desk.
“You should keep your hair like this Bakugo.” Kirishima was in the middle of saying when suddenly he felt a pain in his chest where he had been struck a week prior. He gave a slight hiss, but it was gone almost as soon as it had started. When the pain ceased, he was suddenly back to his normal size and was sitting on the desk with his legs on either side of the blonde. Both boys eyes widened to the size of saucers and blushed darker than Kirishima’s hair.
“Uhm…” Kirishima said. His mouth opened and closed a couple of times trying to find the words to express what he was feeling in that moment.
“Kiri!” Mina was the first to break the deafening silence that had fallen upon everyone at the sudden change in Kirishima.
“Alright everyone settle do-” Aizawa said as he slid the door open as the bell rang, but then he noticed Kirishima and Bakugo. “Kirishima? What happened?”
“I have no idea Sir!” the redhead said not looking at him, his gaze still focused on the heavily blushing blonde in front of him. “One second I was standing on the desk playing with Bakugo’s hair and the next I’m like this!”
“Go see Recovery Gi-” he was saying, but then noticed Bakugo lift his hands to the redhead’s face and squish his cheeks together like he had done the first day that Kirishima had been small. What was he doing?
Kirishima watched the blonde squish his cheeks, both of their faces going redder than before. He couldn’t come up with anything to say. He was enraptured with the look on Bakugo’s face. He couldn’t bring himself to make any noise as he pushed his chair back and standing up started walking away.
No one but Kirishima noticing the tremors in Bakugo’s body as he held control over his quirk by a thread.
Their temporary classroom door slammed closed and seconds later a loud explosion detonated, quickly followed by a loud, “FUCK!”