Rin is a masked girl member of the Supreme Five Swords of private Aichi Symbiosis academy,She rule the school with Satori Tamaba, Mary Kikakujou, Warabi Hanasaka e Tsukuyo Inaba,  after the private Aichi Symbiosis Academy a school only for girl be open to the males. The girls because are scared by the males beggining to  use weapons.  Female students have been violently oppressing their male classmates out of misguided paranoia ever since the school became co-ed and destroy the dignity of males.