Blood Hunt (Sentinel Wars #5)

Hope appeared out of nowhere, naked and alone, a woman without a past. The only thing she knows is that she is imbued with a strange power. It's in her blood. And two men want to posses it. One is Logan, a Sanguiner demon-fighter who needs Hope's essence to survive. The other is Krag, a Synestryn lord whose desire is to enslave Hope, and drain her of the lifeforce. When Hope and Logan both fall prey to Krag, a powerful desire grows between them. But is it enough to thwart their captor's diabolical plan and his demon warriors, and survive a vampire's destiny written in blood?