Nouveau Lich — Christina Winds

Spy. Assassin. Inventor. Phillip Lichner is used to knowing what needs doing and how to do it with skillful efficiency. But with a big brother who is the king of Abaddon and the acknowledged strongest lich ever known, Phillip has always felt second-best. Still, when his brother, King Eric, asks him to come to Earth to get a spy network established before the banished Abaddonites are allowed to return, Phillip can't refuse. But how long is it going to take to recruit spies for magical beings in an unfamiliar world full of magically-blind humans? Then he meets Rebecca and he is no longer quite so impatient to get his task done so he can return to Abaddon.
Rebecca Smythe fought hard for her job with the FBI--against the good ol' boy's club, controlling relationships, and even her own father. She's not about to give it up just because she finds Phillip so intriguing. Minor flirting is all she'll allow rather than risk forming an attachment that would have her defending her life choices yet again. But when a case goes sour and Phillip is the only one she can trust, his unconditional support makes her question her view of relationships--if she can get past the fact that he's not quite human.
Then again, it's not only the banished races that can be monstrous. The humans she chases are far more 'monster' than the handsome lich helping her.