A Matter of Conscience
By Rosemarie E. Bishop, 1999
Series: The Moral Vampire Series

"After more than 500 years, Christian Desmonde is finally going to be reunited with Diana, his sister whom he never knew had joined the immortal world of the vampire. But she is discovered by the oldest, most vicious vampire in existence . . . . . . . Gaetano Minotti, who is also the head of the MAFIA. Only Jesse, an angel and friend of the vampires, has a chance to save her. A Matter Of Conscience is a tantalizing novel that deals with the power of love and the destructive potential of even the simplest lie which can become devastating if left unsettled in truth." (from rosemariebishop.com)