Ok now stay with me here. Roxas is ventus, Terra is Xemnas, and Xion is aqua or something i forgot what they called her. anny way in 358/2 days Xemnas tells Roxas that his real name is Ventus. Xion isn't a nobody. her keyblade was fake. Xemnas is the only real nobody. but because he founded organizationXIII he let "Roxas" and Xion in knowing they weren't nobodys because they were friends. it evplains a lot in all the ansem reports. in KH one and two. in KH two Xemnas is seen talking to the armor of one of the three from Birth by Sleep. That I know for sure. But in a long shot i think that roxas doesn't have anything to do with Sora but maybe a relative. I will look at Soras room in KH one for hints. (it's in one of the begining cutscenes) maybe roxas was a brother or something or a twin. Still working on that tell me what you think.