Piccolo

After training Gohan for a year, Piccolo grows fond of the boy, and sacrifices hims self  to save Gohan in the battle with Nappa. His training also made Gohan more independent and self-confident. His fondness of Gohan is evident throughout DBZ, although Gohan eventually surpasses his mentor in power. Like Vegita, Piccolo wa bad, turned good, and doesn't have strong feelings for alot of the other Z-fighters. He's more of a no nonsense military type.. although his character's personality changes.