popular published books. Unknown to most people, he is secretly a serial killer. A school nurse at Ouba Girls Academy. Touko's frail mother; she's often very gloomy and quiet type of person who often devotes all her time to her household duties. Touko's calm and friendly uncle. He deeply cares a lot for his niece as she is the most precious person to him. Touko's grandfather who seems to be a very grumpy fellow most of the time. He is also the chief physician of a local hospital. A homeroom teacher at Ouba Academy. A highly unassuming person who doesn't stand out very much. He often advises Reiji that the school rules do not allow for much interaction between siblings. However he does appear to sympathize with Reiji as he struggles to deal with the seemingly emotionless students that lack any trace of individuality. A half-Japanese friend of Reiji's who works as a tour guide at the art museum that Reiji and the students visit during a school field trip. The vice principal of Ouba Girls Academy as well as the faculty advisor to the art club. He hires Reiji to search for the missing students at his school and pleads with him to conduct an investigation within school grounds in order to prevent any more casualties. A psychiatrist at the hospital owned by the Kuchiki family. Yui's best friend and classmate. She runs into Yukari and the rest of the art club members a lot. She became rather depressed after her friend's disappearance, and as a result doesn't talk to others as much as she used to. A coroner who forbids anyone to address her as anything but "Natsume-san". Though she can be rather shady with her words and actions, her skill as a coroner is undisputed. Reiji met her during his time on the force, and still relies on her for important information. However, he tries to stay away from her as much as possible, as she tends to require "something" in exchange for information. A private detective based in Ueno. Used to work with Reiji and Uozumi and still helps out his friends when needed. Married to Kazuna, a former client with whom he shares a lot of history. Since she’s currently pregnant, Shugo focuses on less dangerous tasks like investigating cheating spouses and searching for people in order to worry her less. A police officer who