In the Monster’s Wake by Catherine Lievens

The monsters walk amongst us.

Jasper is a former hunter, and that’s what he wants to continue being. There’s a reason he left the family business years ago, but when his mother suggests he look into the string of awful murders, he can’t say no—mostly because he wants to get his father off his back, and Leroy won’t take no for an answer.
Archibald is a PI and a monster. He thinks nothing of accepting the job when the father of one of the recent murder victims hires him to kill the monster responsible, but he doesn’t expect someone else to be looking for them.
He certainly didn’t expect to pair up with a former hunter and fall in love with him.
Things won’t be easy for Jasper and Archibald, and not only because of what they are. They need to find the monster before they leave more death and destruction in their wake, but will they be able to?