Fairlight. The Fairlight Novels, #1

For centuries the witches in the city of Fairlight, and the vampire covens have struggled for power, even though for over two hundred years they supposedly have come to a workable truce. At the age of twenty Velvet Washington, a witch of superior skills, decides the vampires are breaking the spirit of the truce by turning victims in order to increase their numbers. Any witch, she believes, knows the power in numbers.
Unfortunately, the Council doesn't care and insists she mind her own business and stop the night stalking in graveyards. However, Velvet thinks it is her duty to halt the monthly risings of the undead.       Wilder, a master vampire, and his sired partner, Jerome, trail her for a few months trying to figure her out. She is a witch that seems as driven as a slayer. Slayers, who just happen not to reside in Fairlight anymore.
Intrigued by her skills and commitment Wilder approaches her.  Wilder has not lost any of his to her sword, so he can be generous enough to warn her to cease at once because the Coven as a whole, though reluctant to risk incident with the council, will get around to stopping her, and to Velvet the only way a vampire can make her stop anything is to kill her. Wilder finds her attitude ridiculous and tells her the folly of her single- minded prejudice and extreme arrogance.  He tries to convey she is short sighted in what she can accomplish with her talents, and what she could do for Fairlight as a whole community, rather than just for witches.        Velvet ignores her grandmother's advice and warnings not to trust a vampire, especially one she finds so attractive in the moonlight.