Son Gokuu—better known as the Four-Tails—is one of the tailed beasts, currently sealed inside Roushi, a ninja from the Hidden Stone Village. Unlike some of the other beasts, Son Gokuu doesn't get a ton of screen time, but fans often note its volcanic nature and aggressive personality as pretty distinctive traits among the Jinchuriki hosts.
Content compiled by AnimeList.moe from publicly available sources.
