Giko Nokomura is a female student at Nightingale Academy, who carries around her very own chainsaw. One day she begins to be attacked by modified corpses created by one of her classmates, Nero Aoi . She tears her way through the corpses and busts into Nero's hideout. Why is Nero so intent on attacking Giko?! The reason will shock you!After her battle with Nero, she encounters a new enemy. It's the leader of the Nightingale Academy Student Council Guardians, Nemesis.