From The Grey House:
After meeting Vincent and his people though, Natalia reread the journals that spoke of him. Then she slept with the vampire. Now, Natalia wanted to be with him. Alone in her room at the cabin, Natalia had time to think. Though Vincent had threatened to take her home against her will, he didn’t. It was more than she could say for the Slayers. Miguel didn’t even bat an eye when he saw her and found out tonight that she had been captured. The Slayers wanted to win against all odds. Vincent seemed to want her on his side.