Plagued by a recurring dream, young Madotsuki journeys to another world each night. There, she encounters a room with 12 doors. Driven by curiosity and resolve, Madotsuki sets aside her concerns and explores these realms, seeking the reason for their existence. Each door conceals a distinct theme, setting, and atmosphere. Madotsuki discovers that the dream worlds are treacherous and deadly. Will she unravel the mystery of the 12 doors, or will she remain trapped in the dreamscape?