Aoi-sama assigns Shura and Hyakki to assist Karyuu in eliminating a dangerous opium merchant named Chen, but the mission is a ruse to monitor Karyuu's loyalty. After Karyuu confronts Chen and seeks information on a mysterious target, his companions reveal their true purpose. Accusing Karyuu of treason and spying for Gisuke, the two shinobi turn on their comrade, attempting to kill him because his superior strength has made him a threat.