THE CASE OF THE GHOST OUT OF TIME [Raven Lenore, Psychic Investigator #4] by Joe Vadalma

In the fourth novel in this bestselling series, Raven is given an assignment by the demon Lilith. She meets a time traveling ghost, is betrayed by her lover and best friend, visits Merlin's cave, is harassed by vampires, has narrow escapes from death, and falls in love. It's all in a day's work for a psychic investigator. And that's just what happens in the first few chapters!