Elemental Compass by Jaymin Eve

Jacob Compass is stuck in the human world, navigating a peaceful treaty so that supernaturals are not exposed. Justice Winter reluctantly finds herself helping him with this task, all the while dreaming about punching him in his perfect, smug face. Suffice it to say, their coexistence is a challenge in many ways.
Turns out, though, that during this battle against an enemy that they can’t just kill and get rid of–annoying as it may be–they learn that they have more in common than just their fey race. More than the fact that both of them find joy in the fire element.
There’s something deeper that exists in their souls, and maybe, it might just take the end of the world for them to figure out what it is.