Killer Bee is the Jinchuriki of the 8-Tailed Giant Ox and younger brother of the Hidden Cloud Village's 4th Raikage. Bee's father, the 3rd Raikage, sealed the 8-tails within him after it went on a rampage and killed many people in the Cloud Village. Soon afterwards, Bee suffered from the same prejudices endured by Gaara, Naruto and all other jinchurikis.
However, he kept smiling and pushing himself to become the best jinchuriki there could be and during his training on the giant turtle island in the Land of Lightning Bee discovered the Falls of Truth. There he learned how to control the 8-tails in the blink of an eye. Ever since then, Bee has become a beloved hero of the Hidden Cloud Village known as the "Hero of Heroes".