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The days where Kirishima regressed were few and far between, he always found himself tangled up in course work or training and if not that, than taking care of his own little and then some, but he did so and loved to do so without begrudgement. But today he let himself slip into the bliss of his five year old mind because there was nothing tying him to his older headspace. Bakugou went into the city to shop with Mina and Denki, it was a sunday which meant no training and with Momo’s help, he was all caught up on coursework AND homework. He had the day to himself to just be a kid.
The first thing Kiri did when he felt the shift in his headspace was have a shower, big Kiri was sweaty and gross. So with a determined stride and a look of pure concentration, he made his way to the showers where he spent most of the time sat on the floor splashing in the puddle that had formed from the shower that was still raining down on him. Next on his list was a change of clothes, he toddled hurriedly back to his room with his towel badly and very loosely encasing his whole upper body. Once he was back in his room he shucked the towel, leaving it wet on the floor while he rummaged through his drawers for his red, yellow and blue block coloured shirt, his comfy shorts and his crocs.
Once he had found the items, Kiri fought with them to get them on, tripping several times in the process of underpants and shorts specifically. His shirt also managed to make it on backwards but he didn’t care, he had dressed himself! He was a smart kid!
Post wrestling with every item of clothing he was wearing, Kiri set out to find his pet rock, Rocko, to keep him company. Rocko was stashed in the back of Kiri’s bottom drawer along with his plastic dinosaurs and his blocks. With a pout of his lips at how tiny he felt seeing the toys he pulled them from the drawer and dumped them out onto the floor.
He crawled through the mess of toys happily, picking up different dinosaurs and roaring for each one, a loud “RAAAAWR” for the T-Rex, a sort of “moo” for the Parasaurolophus and a raspy chirp for the compies. Each getting a treasured moment in Kiri’s playtime before he moved onto the blocks, arranging and rearranging simple words and the inaccurately spelt names of his friends before smashing his hands down through the names and scrabbling up the blocks once more only to spell their names out again and mutter them to himself.
"Kaminari" He said proudly, looking down at the blocks that spelled "carmenaree."
He beamed with accomplishment before pulling apart the word and spelling more names.
"Bakoogo"
"Meena"
"Serro"
After rounds and rounds of spelling with a brief interval of the carnotaurus attacking the letter W, Kiri began to feel hungry and sleepy. He decided one had to come first so he stuffed Rocko into his pocket and wandered out of his room and down the stairs to the kitchen, counting each step with a jump as he went.
He skipped across the common room and into the kitchen only to stare blankly at the fridge, then the stove, then back again.
"I dunno how to cook.."
With a new problem in front of him, Kiri paced up and down the kitchen and consulted Rocko.
"Snacks! I should've thought of dat"
Kiri gave a huge kiss to Rocko and sat him on the bench to keep watch while he hoarded all of the cookies from the pantry.
In between the rustling of cookie wrappers and his own mischievous giggles he failed to hear when someone entered the room until he heard them clear their throat as if to gain his attention.
"Umm"
Kiri said around a mouthful of cookie.
"Rocko -ou were shposed to keep watch" He pouted, swallowing the last of the cookie.
"You raiding the pantry, little guy?" Sero smirked.
Kiri shook his head, and looked down at the packs of cookies in his arms like they had just betrayed his trust.
"Let me help"
Sero grabbed the cookies out of Kirishima's arms, holding them in one arm and grabbing the little boy's hand with his free hand.
They scurried quickly back to Kirishima's room, passing Tenya on the way who gave them a gentle reprimanding look for their arms full of cookies which they paid no mind to at all.
Kiri immediately delved into the packs of cookies, ripping apart the packets to deal them out to Rocko and all of the Dinosaurs before grabbing some to stuff into his mouth.
"You're gonna give yourself a tummy ache if you eat too fast, little guy." The older boy informed.
"NO." Kiri pouted, and turned his back to Sero, biting loudly into another cookie to make a point that his tummy absolutely was not hurting at all and Sero absolutely was not right. But then his tummy growled announcing it's growing pain and Kiri scowled, poking it. "Traitor."
He turned back to Sero and pushed the cookies toward him begrudgingly. "Here."
"Thank you" He responded with a drag on the A as he pushed the cookies behind him and put of Kirishima's line of sight. "What have you been doing for up here bud?" Sero said, hoping to redirect the conversation. "PLAYIN WIT MY DINOS" Kiri beamed, mind now totally pulled away from the cookies and the exhaustion that was waking heavy on his body as he excitedly recited the names of the different dinosaurs.
"... and this one is a spinosaurus aegyptiacus and this is a pachycephalosaurus and and mosasaurus and this is my velociraptor"
Kiri waved his hands excitedly and stared at Sero in an anticipation with stars practically glittering in his eyes.
"Wow- those are some big words" the older boy stated with a mixed look of confusion and amazement. "Thanks for the info little bud."
Kiri nodded happily, yawning as he did so. Now that the excitement had worn off, the exhaustion was hitting him full force.
Sero watched with a smile as Kiri yawned and scrubbed at his eyes. "Are you sleepy big guy?"
Kirishima gasped and shook his head before stopping and nodding, admitting that maybe he was a little tired.
Sero gave his hair a ruffle and suggested they begin packing up the toys so they could have a nap at the same time.
Kiri helped, scooping up blocks and dinosaurs by the handful and dumping them back in his bottom draw messily. "Done!" He announced happily bouncing in place and standing up to go jump onto his bed. "That was pretty quick, faster than Iida, I think" Sero said with a smirk.
Kirishima looked absolutely in awe, he had to tell Iida about how fast he was!! In one swift motion he was off the bed and out the door, sprinting down the hall as fast as his crocs would carry him. He skidded to a halt outside Iida’s room and knocked loudly, “SPEEDY SPEEDY SPEEDY.” Iida opened the door with a small smile.
“Kirishima.”
“SERO SAYS I'M FASTER THAN YOU”
Kirishima bounced in place, beaming up at Iida like he had just told him the most insane and cool thing ever.
“Did they now?” Iida raised a sculpted eyebrow as Sero appeared behind Kirishima with their hands up, “I’m innocent dude.”
“Liar liar pants on fire” Kirishima teased, turning to face Sero, crossing his arms like Iida. “did too.” Sero gasped in mock hurt and pressed the back of his hand to their forehead, “Betrayal from my best little buddy.”
Immediately Kiri unfolded his arms and hugged Sero. “I take it back, Sero never said anyfing like dat, we’re going now.” he pulled out of the hug, grabbed Sero’s hand and took off down the hall giggling his little head off.
“Nice save buddy.”
Kirishima giggled mischievously and climbed back onto his bed. “Thank you,,,,, can you tuck me in?”
Sero really needed to be getting back to the exam he was studying for but Kirishima’s big pleading eyes held him dead in place until they said yes. “Of course.” Sero pulled the camo blankets up over the little boy and handed him the dinosaur stuffie that was sat on his desk.
“You ready for nap time?”
Kiri nodded as Sero got up to turn off the light before shaking his head. “NO” he shrieked, pulling the covers over his head. Sero felt his heart melt in their chest as they switched back on the light.
“Are you scared of the dark Kiri?”
Kirishima nodded softly, tears welling in his eyes. “‘S not very manly but,,, scared there is gonna be villains under my bed”
Sero took a seat next to Kirishima, pulling the boy into a tight hug.
“All heroes are scared of something. Do you have a night light?”
Kiri nodded, pointing to the fire lamp next to his desk. Sero reached across the room and flicked on the nightlight before hitting the main light switch with a bit of tape to turn it off.
“I’ll stay with you until you fall asleep.”
And stay they did, curled tightly around their young friend until he was sound asleep, exam prep completely forgotten.