Tsumugi Shirogane is an ultimate cosplayer high school level. She's a participant in 52nd(v2) game, and now she's the mastermind in 53rd game, which means the protagonist, Kaede was false executed by the mastermind. Oh and also, Tsumugi Shirogane likes Male Y/N(M/N for short), since she's interested that he likes her cosplay, she decided to make him the mastermind too.