The Great Dog Demon was a powerful yokai lord who ruled the Western Lands and was known throughout Japan. Never formally addressed with a name, he fathered two sons by two different mothers: Sesshomaru from his consort, an unnamed dog demoness, and InuYasha from a human woman (unnamed in the manga, but named "Izayoi" in the third movie). The Great Dog Demon is first mentioned in chapter 12 of the manga as InuYasha's father, "a demon dog that prowled the lands of the west". The Great Dog Demon's major foe in the manga was the dragon Ryuukotsusei, whom he could not kill but sealed onto a cliff face with his claw; Myouga calls this battle the "cause" of his death.