From The Grey House:
A shudder passed through Vincent. “It would be a great joy to take her on if she turned on me.”
Joseph gave a short laugh, shaking his head. It was always impossible to deal with Vincent when he was in the grips of an obsession.
Vincent watched in silence as the shadows passed in front of the nearby trees. “It’s time to leave this place. My plane is waiting, as is my sire.”