If it wasn't for her hot headed brother Kirishima would have more of a chance with her. Bakugou however, was protective of his younger sister and his bad attitude didn't really help either. Kirishima cared for (Y/n). She was sweet and she loved being friends with people, she was basically the opposite of her brother.
As he was stuck thinking of said girl, Kirishima heard two voices out in the hallway.
"Katsu, you shouldn't be so mean to everyone!"
"Damn it, even you're going against me?"
He recognized the two voices as the Bakugou's. They were close for siblings, Kirishima and everybody else knew that. It was odd to hear them argue.
"I'm not going against you, I'm just saying you should be nicer to Kirishima. He is your friend, isn't he?"
Kirishima felt his heart jump in his chest as he pressed his ear against the door so he could possibly hear more of his loves praise.
Katsuki was silent.
Heavy footsteps were heard and the sound of a slamming door soon followed. After, it was just quiet. He wasn't sure if she was still there, but he guessed she was. He wondered why she hadn't left yet.
He jumped back when the door he was pressed against started to slide open. He nervously looked up only to see the person of his affections.
"Kirishima? What are you still doing at school?" Her voice was soft but there was no way she didn't know he was listening in on her and her brothers argument.
He knew it was in his bets interest to answer her, so he came up with a simple answer.
"I was looking for you, actually."
God, saying it out loud made heat flush on the back of his neck. She was staring at him with confused eyes.
"Looking for me? Why?"
He wasn't expecting her to ask him that.
He couldn't come up with an answer so he simply looked around nervously.
"You're really bad a lying, you know that?" The teenage girl said, giggling slightly to herself. He wondered, just for a moment, that maybe she liked him just as much as he liked her.
"Well, now that you're here, I guess I should tell you."
She was silent before a guilty look overcame her usually happy expression.
"I'm moving to another school."
"Katsu thinks I'm too distracted here, so I'm moving to another school."
His heart felt like shattering.
"... you can't."
"You can't leave! Not now. We've gotten so close. I've gotten to know you more and more, you can't ruin all of that by leaving!"
He was angry, she could tell. She was too, in a way, but she loved her brother and she knew he only had her best interest in mind.
While she was thinking she felt the red haired boy grab her and bring her close to him. She felt a pressure on her neck and she blacked out immediately.
"I didn't want to do this, but you gave me no choice."
This probably sucks because I can't really see Kirishima as a Yandere. He's too much of a sweetheart!