According to his official biography, Vega was born in Spain on January 27, 1967. He stands 186 cm (just over 6' 1") and weighs 72 kg. His blood type is O. He is skilled at climbing. He likes himself and other beautiful things. He hates ugly things and his biggest fear is damaging his face (which is why he wears a mask while fighting.). His fighting style is a combination of ninjutsu, bullfighting, and claw fighting.

Vega is from a Spanish noble family, but they lost everything they had. His mother married another nobleman for his money, not his looks. As he grew, Vega learned bullfighting, a tradition in his family. He went to Japan and learned ninjutsu, a style he believed meshed well with his natural grace and agility. Combining bullfighting with ninjutsu, Vega went into the underground cage fighting circuit, and quickly became one of the best. His stepfather murdered his mother because he felt she didn't respect him, and Vega killed him in return. The incident damaged his mind, and he developed a dual personality: honourable nobleman by day, sadistic masked killer by night.