Arakawa Ao lives happily on his own and hardly ever leaves Shimokitazawa, where he works at a vintage clothing shop, goes to occasional concerts and hangs out at his favorite bar. Then, he gets an unusual request to appear in an independent film.
High school freshman Akihiko has a stutter, which makes him the target of bullying by his classmates. One day he sees his beautiful and brainy classmate Hikari killing a cat. Hikari confesses her desire to murder people and proposes that they kill Akihiko's tormentors.