A high school boy and girl: Itsuki Kamiyama and Yoru Morino are "GOTH," who have an obsessive interest in the dark side of humankind. One day, Yoru picks up a note in a cafe that serves as the meeting ground for geeks. Included on the note are all the details about the bizarre murder cases that have occurred in many places recently. Intrigued by the cases, she asks Itsuki to go to one of a homicide scene, where they go in search of an unfound dead body.