The Birdcage by Arianna Fraser

Black Heart keeps me in the Birdcage, high above the blasted remains of the earth after the Night Brethren plunged us into darkness. At the gate of his mansion, the Shadows wait to tear screaming humans into pieces of blood and bone. In the Birdcage, the vampire who keeps me is growing impatient. What does he want? My blood? My soul? I don’t have long to decide whether to take my chances with the Shadows or find out what Black Heart intends to do.

To make it worse? He’s not the only monster who wants me.