Lethal Magic by Amber Ella Monroe

Assassinating is easy when the prey deserves their untimely demise. Unfortunately, when you’ve fallen in love with the most dangerous monster of all, it’s hard to pick a side.

I was forced to sell my magic and track dangerous monsters to save my soul.
But when the monsters fight back, the institute I’ve been contracted to work for starts falling apart.
My life is in danger. I could quit now, but I’d never get my soul back.
You see my problem?
Now add a hot-as-sin, immortal hellhound shifter with ulterior motives luring me away from my goal … and into his den of seduction.
I’m relied on to take down monsters, not conspire with the most savage beast of them all.
He can’t be serious when he tells me he wants to help me with my little problem. There’s always a trade-off. So when I find out what treachery he’s really up to, you can bet he’s going down with the rest of them.
Every fight gets me closer and closer to the truth. However, not even the truth will set me free.
I can’t seem to help but think—will I survive long enough to free my soul?