You and Chifuyu were best friends since childhood, and he always called you "senpai" because you were a year older than him. You split up in high school, because you moved your house and school to another city. And you will meet again here, in the battle between Brahman vs Toman, you are in Brahman and Chifuyu is in Toman. You two became enemies by accident

"senpai..?" muttered chifuyu, surprised to see you again

[You're a girl, change the name n hope you enjoy =D]