Blood Wars Trilogy by T.A. Miles (epub, mobi) [BluA]

Blood Lillies
Blood Song
Blood Reign

Summary:
For Korsten Brierly, life already seemed complicated enough. Disinherited from a young age, helping to govern a town of strategic significance to warring countries, keeping his affair with the local governor's son a secret....

When a demon hunting mage arrives at his doorstep at the same time gruesome murders begin, Korsten finds himself quickly swept away by a tide of events and discoveries beyond his darkest dreams. Caught up in a war much deeper and far more dangerous than he ever would have believed it to be, Korsten is forced to abandon the life he knew and everyone in it. Summoned to a duty that terrifies him, by powers he can't ignore, he begins a journey into understanding his own soul and how to protect the souls of others from demons bent on possessing, poisoning, and devouring them through methods that are gradually decaying the world they live in. Struggling to stay afloat in a maelstrom of ancient forces, his own emotions, and dangerous political games, Korsten commits himself to the task, for the sake of his soul and his sanity, and for the sake of the lover he was not supposed to have...a man possessed by ambition and by a demon with goals of its own.