Whether set in the future or the past, it is a world of fantasy and horror lurking in the shadow of a demon city. Within the city, a series of mysterious incidents that science cannot explain have taken place. To resolve these incidents, three girl detectives with special abilities are brought together. Hayama Kotono. She is an orphan residing in a convent. Shirafuji Natuski. She is Kotono's classmate and a pop idol. Hijiri Misaki. She is a mysterious girl who battles the nightmares of her past life. Those who seek to bring Judgement Day to the world. Those who seek to save the world. Which represents justice, and which represents evil? When Kotono encounters a boy who has lost his memory, the story's wheel begins to turn, albeit slowly. Then, as they solve the mysteries, the three girls will confront a fate that will influence the existence of humanity.