He is the lost father of Goku Jr. and son of Pan. He became lost in the Hyperbolic Time Chamber while training and never returned, which is the reason why Goku Jr. is scared to fight. He was very powerful and vowed to protect the world while Pan became old. So one day he went to train to hone his many Super Saiyan abilities. Sadly, though, he became lost and remains there to this very day.