Vegeta........Ok, I refused to call him that, coz I think his japanese name, Bejita, sounds cooler to me!!! In the beginning of the story, Bejita is an enemy. After so many situation, Bejita ends up teaming up with Goku and others to defeat Freeza. Then later he stayed in Earth, developed a relationship with Bulma and has a son, Trunks.
Bejita is a proud prince of Saiyan. As a prince, he is unable to accept the fact that Goku is stronger than him. He always trained himself in order to defeat his rival, Goku. Yet living in earth, getting influenced by Goku, Bulma and Trunks, slowly Bejita's evil heart melts. In the end, Bejita stymies his pride when he calls Goku the number one warrior.