Genbu is an enemy in the Manga/Anime Yu Yu Hakusho, and a member of the Four Saint Beasts. He's also known as; The Stone Beast.
Genbu is a golem-like demon that kinda resembles a tortoise with a scorpion's tail.
Yu Yu Hakusho
Genbu was the first Saint Beast that Yusuke and his allies first encountered. He was challenged by Kurama. Because of his power of becoming one with any rock, and reassemble himself he would have the advantage. But in the end, Kurama manage to find Genbu's weak spot and destroyed it, killing Genbu.
When Yusuke and his friends/allies encountered the second Saint Beast; Byakko, he claimed that Genbu was the weakest of the Saint Beasts.