Katsuki Bakugou x little sister (OC)

Going to school

"Nii-Chaaaaaannnnnnnnn!" 

Heads turned towards a brother and sister duo, the latter crying, red cheeks puffed out and latching onto her older brother who bore a nonchalant face.

"Don't 'Nii-Chan' me all cutesy like that and get your a*s into school." Katsuki grumbled shaking Masumi of him.

It had been a struggle, all weekend Sumi had been excited for school and bragged about it to virtually anyone she came across but the nerves had seemed to caught up with her. A new place, a new school, new friends. It was all a bit too much.

"Eri have a good first day." Kirshima also came to drop the two children off, he ruffled Eri's hair and gave her a hug.

"See look, you have Eri, you aren't the only new kid here." Katsuki bargained as he wiped the tears off Masumi's pouty face, "Ok blow" he said as he brought his handkerchief to her nose, "Ew disgusting" he gave a contorted look at his handkerchief as Masumi frowned.

"Katsu-nii I don't want to leave you." Masumi sniffled, "You'll be lonely."

"Katsu-nii won't be lonely cause he has me." Kirshima said proudly pointing to himself.

"Call me that again and I'll murder you." Bakugou threatened.

"Come on Mi-Chan we can do this!" Eri cheered her voice wobbled with worry but determination sparkled in her eyes.

"Yes you can do it!" Kirshima cheered alongside her.

"Yea you can do everything and anything  cause you are part of MY blood line." Bakugou rolled his eyes.

He then bent down to her level and cupped her cheeks into his palms, "You are Masumi f*xking Bakugou you're a queen amongst peasants , amongst the mutts that crawl on the ground you reign supreme and don't you forget it." He growled as Masumi gave a determined nod.

"Alright now go you brat." Katsuki gave her a little shove and straightened himself up.

"Let's go Eri-Chan." She held tightly onto Eri's hand and ran off but soon turned back, waved, and continued to run.

"Aww your a great big bro....Katsu-nii." Kirshima laughed.

"Alright your dead." Bakugou screamed as Kirshima ran away with Bakugou chasing behind him.

In The School

"Alright class today two new students will be joining us." A meek looking teacher with thin brown hair and gentle grey eyes announced.

"Please introduce yourself."

"M-my name is Eri and I hope we can be friends."

Masumi controlled her breathing wiped away some stray tears and began "My name is Masumi and I'm a bad bish." Masumi gave a wide toothy grin "And Eri-Chan is my most bestest friend." She declared as Eri gave an embarrassed blush beside her.

"Masumi-Chan who taught you that." The teacher asked worriedly.

"My Nii-Chan. He's the coolest." Masumi nodded.

"Oh well that's nice but maybe try saying you are an 'amazing person' instead." The teacher offered.

"Oh ok thank you Sensei I think you are cool too!" Masumi smiled brightly as the teacher smiled back and ushered them to their seats.

"Eri-Chan let's go make friends." Masumi stated after the lesson had finished, it was play time and she began to stand up from her chair but  it seemed she didn't have to necessarily 'make' friends as a crowd of people already started to hover around her.

"What your name." Masumi pointed at a long haired brunette with soft doe brown eyes.

"Oh me? I'm Chiyo nice to meet you Masumi-San." She squeaked nervously.

"Chiyo that's a cute name, your my friend now." Masumi declared stepping to the nervous looking Chiyo and grabbing her hand, "Chiyo-Chan do you want to be my friend?" She asked tilting her head.

"Y-YES I'D LOVE TO BE YOUR FRIEND!" Chiyo smiled jealous glares were sent her way from the people around them but she still seemed to sparkle "Here let me introduce you to my other friends."

"See Eri, it's so easy to make friends, ok you make friends with the next one." Masumi whispered in Eri's ear as she nodded hesitantly as they both followed Chiyo.

"Here, she's Ayane," Chiyo said pointing towards an unbothered  girl with short pastel purple hair, "And that's Hoshiko!" She said and pointed at  strawberry blonde girl with equally short hair and a  fringe covering her eye, she waved politely.

Masumi gave Eri a little shove.

"H-hi my names Eri, I-it's really nice to meet you Ayane-San." Eri trembled with a crooked smile and held her hand out to the purple head.

Ayane looked down at the extended arm and her eyes widened and face paled, "Oh my goodness!" She gasped.

"W-what?" Eri stuttered.

"Your hand....there is something there!" She exclaimed.

Eri gasped and started shaking her hand and rubbing it, "Is it...is it gone..." Eri whimpered checking her hand.

The girl suddenly smirked, which then broke out into a grin which THEN broke out into fits of laughter and giggles.

"W-what?" Eri asked.

"Pfft there was nothing there I just wanted to see how you would react." Ayane chuckled.

"Hey that's not nice." Masumi stepped in front of Eri and pouted.

"Aww, cute." Ayane smirked stepping closer to Masumi.

"Your seriously annoying." Masumi stated angrily.

"And your little friend is seriously gullible." Ayane shrugged.

Masumi narrowed her eyes and was about to lunge at her when Hoshiko stepped between the two, sweat-dropping.

"Don't mind Ayane she's always like that, she means no harm." 

"Yea right." Masumi gave Ayane a dirty look whilst Ayane just stuck her tounge out at her smiling.

"Hi Eri-Chan I'm sorry Ayane's so mean." Hoshiko peaked behind the raging Masumi and gave her a comforting smile.

"It's ok I don't mind." Eri smiled reassuringly.

"Ko-Chan I'm not meannn~" Ayane said sarcastically.

"Let's try and talk about things we are interested in," Chiyo nervously intervened, clearly they all started on the wrong foot but she seriously wanted to befriend Masumi, not wanting this opportunity to pass she had to change the subject. "Personally, i love baking with my Nee-San." 

"You have a Onee-San lucky you!" Masumi gasped, "Still she's probably not better than my Nii-Chan!" Masumi nodded proudly as both Eri and Chiyo nodded their heads in agreement, both would probably agree with whatever Masumi said.

"I like music and helping my dad in his studio." Hoshiko stated. "Ayane?"

"Well.....I love myself and chocolate.....and eating chocolate." Ayane said.

"I like playing with Eri, and I love being with my a Katsu-Nii and his friends." Masumi stated.

"Katsu... is he your brother?" Hoshiko asked.

"Katsuki, and yea he is." Masumi said proudly.

"I really like Masumi and all my friends...and drawing." Eri shyly muttered.

"She really good at drawing." Masumi exclaimed putting and arm around Eri, "Like super duper amazingly good!"

"Really wow you must be amazing Eri's San!" Chiyo exclaimed as Eri blushed.

"Alright children break is over time for the next lesson." The teacher called .

Sorry this feels rushed but I tried if you enjoyed it pls vote and comment your support helps me keep going T-T.