Nagi and Shizuka have managed to avoid a grisly death at the hands of two assassins-siblings from Nagi's past life enrolled at the mysterious ACADEMY. To make their escape from their terrifying duo, Shizuka moves them across Guicheng Island, from one safe house to another. But Nagi's whereabouts have reached the ears of the leaders of the ACADEMY, an iron-fisted administrator known only as Sensei, who dispatches a prodigy at the art of murder to track Nagi down once and for all: the rampaging rookie, Uzu!