Necroscope: Defilers

Jake Cutter is reluctantly learning how to be a Necroscope - how to use the Möbius continuum to travel instantaneously from place to place, how to talk to the dead - but the dead don't like him much. It seems Jake's got a hitchhiker in his mind, a dead vampire named Korath. But since Korath holds the key to the Möbius equations, Jake can't just kick him out... In Australia, Jake helped E-Branch destroy the aerie of the mind-master, Nephran Malinari, one of the trio of Great Vampires who came to Earth from the vampire world.
Malinari escaped and went to ground with the hideously beautiful Lady Vavara. Vavara has taken over a holy monastery on a beautiful Greek island and turned the nuns into most unholy creatures of fearsome appetites for all things carnal. But Jake wants revenge against the Italian mobsters who killed the woman he loved. As far as he's concerned, E-Branch can search for Malinari, Vavara, and the metamorphic Lord Szwart without him until he's satisfied his own bloodlust.
But it seems vampire-hunting is truly Jake's job now - the men he's trying to kill aren't men at all but vampires hidden for two generations in human guise!To defeat them, Jake will need every weapon in Necroscope's arsenal, including the power to call the unsleeping dead out of their mouldering graves...