Heavily adapted from the 2008 erotic visual novel by Innocent Grey, the story follows private investigator Tokisaka Reiji through a grisly mystery set in postwar Japan. It is the year 1956, and the Tokyo police bear witness to a recurrent tragedy. The dismembered limbs of different young women appear again and again, sans bodies. Thus Reiji is sought by Uozumi Kyouzou, his childhood friend and former colleague in the police, for assistance in solving the case and preventing any further bloodshed. Meanwhile, the enigmatic Kuchiki Touko, a student of Ouba Girls' Academy and classmate of his sister Yukari, has a peculiar request for him of her own.
