Sennin

The Sennin is an unnamed immortal from Tibet, who is an old friend of Medama-Oyaji. When in the form of a Youkai dog (妖犬 Yōken) he was called Kuro (クロ, lit. Black) in the manga and Tarou (タロー) in the anime. In the manga, the Sennin is an elderly man with long hair that has one strand standing. He wears a robe, covering most of his body, and stands with a wooden staff. In the 1985 anime, the Sennin is an elderly man with pale skin, long white hair with one strand spiraling up, and a thin moustache. He wears a blue robe that covers most of his body, save for his barefeet, and is always carrying around a wooden staff. (Source: GeGeGe no Kitarou Wiki)