Vampire Bytes — Linda Grant

The eagerly anticipated new vampire computer game, Cult of Blood, is ready for release when its lead programmer disappears--along with the game's vital source code. Also missing: teenager Chloe Dorn, last seen playing a vampire LARP (Live Action Role-Playing) game on the streets of Palo Alto, California.

As intrepid P.I. Catherine Sayler hunts for them, the programmer's body is discovered-drained of blood, with two small puncture wounds in the neck. But Chloe is still missing, alone in the dark world where kids play at violence and the malevolence of a murderer will soon hurl them into a nightmare....