Y/n Kocho is the younger sister of Kanae Kocho also the older sister of her adoptive little sister Kanao Tsuyuri also the adoptive sister to Aquamarine Hoshino and Ruby Hoshino. After an obsessive fan killed her parents she decides to join the entertainment industry along with her sister in order to find their killer but after Ai's death she sets her foot on revenge till when she was 14 and her sister Kanae was killed she promises to kill her sister's killer.