Feast of Fools by Rachel Caine

Summary: In the college town of Morganville, vampires and humans have learned to live in relative peace. Still, students like Claire Danvers know that after dark, studying can take a backseat to staying alive. But the tenuous good-neighbor policy is really turned on its head with the arrival of Mr. Bishop.

Bad to the bone, the ancient old-school vampire cares nothing about harmony. Staying at the top of the food chain is enough. What he wants from the town's living and dead is unthinkably sinister. It's only at a formal ball attended by vampires and their human dates that Claire realizes Bishop's plan---and the elaborately evil trap he's set for the warm-blooded souls of Morganville.

Wow what an creative writer Rachel Caine is. This book is my favorite so far.