Deadly Enemy Nagumo reveals to Shinpei a Shadow murdered her family 14 years ago, causing her to leave the island and change her name, later publishing a series of books about the experience. Nezu reveals that if a Shadow who has copied someone is killed, that person can never be copied again. Nagumo goes to Shiori's home to kill Shadow-Shiori and her Shadow parents. Based on her behaviour, Shinpei suspects the trauma of losing her family caused Nagumo to develop two personalities, one being the sister Hizuru who wrote the books, and the other being her murdered brother, Ryuunosuke. Nagumo kills the parents while Nezu and Shinpei catch Shiori in a trap. She admits she was the Shadow who killed Ushio and that once their plan is complete her and her family can go home, so Nagumo kills her. Nagumo confirms she has two personalities; she is Hizuru most of the time but Ryuunosuke comes out when she cannot cope or in a fight. Nagumo is their joint fake name and they communicate by recording messages on a tape recorder. Shinpei returns home and finds Mio cooking, which she never does, causing Shinpei to realize his actions have somehow changed events. As he sends her out of the room, trying to return events to normal, Shadow-Ushio suddenly appears.