Hidden by Blood(2011)

Michele HaufCaridad Piñeiro

Deep within the forests of the Pacific Northwest, two vampire coalitions battle for supremacy--Guardians who safeguard humanity and Darkbloods, rogues who will stop at nothing to satisfy their craving for the sweetest of human blood.Now, former Army Ranger Finn McKentry finds himself imprisoned as a blood slave, forced to submit to an enemy more powerful than any he's encountered before. Only Brenna Stewart, the woman he'd loved and lost, can set him free--but the secret she harbors might lead them down the most dangerous path of all...