During the Edo period, Ichitarou, a young nobleman, is confined to his home due to poor health but is safeguarded by supernatural protectors Shirasawa and Inugami. Ichitarou's life changes when he stumbles upon a murder scene while secretly venturing out one night. This event is followed by a series of inexplicable murders in Edo, prompting Ichitarou to collaborate with his demon guardians to identify the perpetrator.