The darkest torment

Baden, having spent centuries in purgatory, is now bound to the king of the underworld and quickly devolving into a heartless assassin. When his mission goes awry, he finds himself saddled with dog trainer Katarina Joelle, someone else's bride, as his hostage. Katarina is plunged into a war between two evils, with a dangerous protector--but is he more dangerous to the monsters he hunts, or to her heart?