Krillin & Goku used to be enemies in the very early episodes of Dragon Ball, but they soon became best friends that no one could coem between. Krillin and Goku both trained with Kame Sennin(Also known as Master Roshi). In Dragon Ball Z Krillin wishes Andriod 18 to a human so he could marry her, and he does and he also has a little girl named Marron.