Detective Kisaragi Toko of the Eleventh Section of Tokyo Metropolitan Police Department’s First Investigative Division was instrumental in solving the case of Toremi, the serial murderer who shocked Japan. Although one year has passed, the trauma she suffered at that time still affects her. One day, a bizarre murder occurs in a room that has turned a deep red. Toko and Assistant Inspector Takano Hideaki proceed with the investigation based on clues
