Castle Of Night: Mortal's Vow

To pay off her father's gambling debts, a young human woman named Leah is handed over to a vampire castle and made the Blood Count's blood-slave. Forced to live among the creatures of the night, she must find her footing in a house where her life now belongs to someone else. Her situation grows more tangled as she is pulled into the Count's world of magic and danger, where every choice carries a cost.