Moonstriker

I've spent the better part of a decade trying to save the world.
Twice a century, Mount Slate threatens to erupt, and for my entire life, the four families in charge haven't seemed to care about their impending doom.
So it fell to me to try to fix things. To make peace.
Me, a man whose greatest skill is pissing people off so much that they challenge me to a duel, and then killing them in that duel.
Now the moment is here, and my clever stone is telling me that one man—a sweet, innocent, infuriating judgmental bastard—is the only one who's capable of saving the world. And I have to help him do it.
I'm starting to wonder if the world is even worth saving.
Moonstriker is the last in a series of four books, starring one cynical not-quite-assassin, one ray of sunshine, and one very grumpy mountain. It features both Aubrey and Kit's HEA, as well as the conclusion of the overall series arc.