Y/n is Momo’s twin sister and has the same quirk; creation. Today it is Y/n’s first day at UA and surprisingly she was in class 1-A the class Momo is in

Aizawa: “everyone calm down and Bakugo stop yelling, today we are having a new student and Momo you know her. Y/n you can come in” he said as everyone looked at the door and Y/n walked in

Momo: “sister!”

Denki: “Momo has a sister!?”