You know how I said Zero was human? This is only partly true. The real reason Yamato chose Zero was because Zero is Vergil's illegitimate son. Once before, Vergil fell in love with a beautiful priestess, despite that she was human. She too, had fallen in love with Vergil. They bore Zero, but upon realizing what he did, Vergil left Zero and his mother, while Zero was still in the womb. He did this because he felt that having feelings such as love would make him weak. Zero was born, and his mother and him moved to Tokyo. His mother did this to try to forget her past. Soon enough, she forgot about Vergil, never telling Zero about his father. Zero took after his mother, having black hair and hazel eyes. When he died, Yamato sensed a blood relative of its old owner near it, and found Zero. Zero took Yamato, as he headed down to earth. Zero's demonic blood awakened, changing his appearance, making his hair white and his eyes sapphire, to make him look more like his father. Due to this, he also gained the ability to use styles. Few demons know of this fact, and even fewer care. Same with the angels. No humans know of this, other than Vergil's brother, Dante. Soon, Zero will have a catalyst in his life, that will make him choose whether he wants his life to be the same, or to follow down the dark path of his father, and go after power, no matter the cost.