The Darkest Assassin (Lords Of The Underworld 14.6)

Fox is a demon-possessed immortal with many talents.
Ability to open portals—check
Power to kill the most dangerous Sent Ones—check
Scare away any man who might want to date her—mate
Now, the keeper of Distrust has been marked for death, a winged assassin with rainbow-colored eyes tracking her every move, determined to avenge the males she accidentally decimated. If only she could control the desire to rip off his clothes…

Bjorn is a fierce warrior with many complications.
Tragic, torture-filled past—check
A wife he was forced to wed, who is draining his life force—check
Ever-intensifying desire for the enigmatic Fox—mate
Never has he hesitated to exterminate an evil being. Until now. The sharp-tongued female with a shockingly vulnerable heart tempts him in ways no one else ever has, threatening his iron control.

But, as Fate itself seems to conspire against the unlikely pair, both old and new enemies emerge. And Fox and Bjorn must fight to survive.

And learn to love…