Princess Taira Chiyo, marked since childhood by an incurable affliction, travels a war-torn Japan in search of immortality. Her quest leads her to Uratarou, a man reborn from a corpse some eight hundred years ago who can no longer die and wishes only for an end. Chiyo asks him to make her immortal; he agrees to travel with her instead, drawn into her path as demons that feed on human despair close in around them.