Rex was born with inactive witch blood inherited from his mother's side. As he grows older, he becomes more and more conscious of this part of him thus making it more and more active. He has been expelled from every school he ever attended since he was 8 due to him playing around with human lives. Rex wasn't always a skirt chaser. He just interpreted the wrong message when his mother told him to hang around people more cause he seemed too anti-social after the suicide incident. It just grew into an enjoyable hobby as time passed.