Tokito Tokitsukasa and his step-sister Kiriko are living in the Imperial capital of Tokyo when they are forced to marry by their grandfather. However, Kiriko has a sense that something is wrong and suspects that her family is keeping secrets from her. Meanwhile, a notorious thief called Shiou manages to escape from the authorities one night and crosses paths with a mysterious girl who bears a striking resemblance to Kiriko. This three-volume gothic horror series follows the turbulent destiny of this singular girl.