Rei Background: Rei is a childhood friend of Takashi, Y/n, and Saya. She used to date Takashi but ended breaking up with him because of an argument they had about Rei repeating the grade. She discuss her problems with Y/n which she greatly enjoys because Y/n can understand her better than anyone she knows. Which she start having feeling for him but kept it hidden as she started dating Hisashi.

Saya: Saya is childhood friend of Takashi, Rei, and Y/n. She is a rival to Y/n when it come to smarts ever since they where kids. She enjoys her rivalry because it means having a connection to one another with Y/n. She secretly has a crush for him that she keep to herself until she feels like she's ready.

Takashi: Takashi is a childhood friends of Y/n, Saya, and Rei since elementary school. He's now the ex boyfriend of Rei since they had an argument about her repeating the grade which resulted in them breaking up, to be honest I don't think this was the first time they argued. He good friends with Y/n and they treat each other like brothers, who have each other backs.

Saeko: Saeko and Y/n have been sparring partners since the beginning of school semester when he came across her sparring. He took an interest in her with kento practice, which she greatly appreciated on showing him how to use a sword properly. Since they have a daily routine on meeting each other for sparring sessions.

Hirano: Hirano is a friend of Y/n ever since Y/n protected him from the bullies of the school and Shido himself who put him down. They share a common interest in guns and hang out after school to go to arcades to have fun while exploring magazine about gun issues.

Shizuka: Shizuka and Y/n are good friend to each other and help her in the nurses office. Which she deeply feel excited to see him come by to keep her company or help her out since the school know her as an airhead. So it make her feel important whenever Y/n visits her and compliments her on her action. She started develop feeling for him since he make her feel special besides her friend Rika.