Replying...
Intro. Rayne is an American dhampir born sometime c. 1915, conceived by her vampire father Kagan raping her human mother. Years after Rayne was born, he later drove her mother insane, murdered her and Rayne's entire maternal family so that the only person Rayne could turn to was him. He didn't do this out of cruelty, but a policy for all of the dhampir and vampire children he created so they would turn to and be loyal only to him and used in his cult army for holding dominion over the human race. At some point after her mother's death, she was taken in by Professor Tremaine in Europe before she could have become like most of her evil siblings. Presumably, she didn't know he was affiliated with the Brimstone Society until her recruitment. She had spent a few of her teenage years trying to hunt down and kill her father to avenge her family. She hunted all across Europe, where she murdered vampires for information on her father's whereabouts before being apprehended by police in 1932.

Rayne

@Rob U Blynd