Marina Alexa Summers, born as Marina Alexa Coppola is a vampire member of the Volturi coven and student of New Moon high school, located in the almost unheard of Breaking Dawn village.
There's not much to tell. She lived a happy life. She had to go to anger management classes.
What her parents never told her, though, was that her real father had in fact been a demon. One day, she came home, and her parents had been drained of their blood. A rogue vampire.
The vampire tried to kill her in turn, but the minute he sunk his teeth into her skin, he sensed the poison in her blood. She was a demon. He couldn't drink her blood, so infected her instead.
The pain for her was ten times worse than in had been for anyone else, because of her demon side.
She was found in her devastated home by Felix, who had been tracking the rogue vampire for some time.