Monster Hunter International by Larry Correia
Monsters are real. But Monster Hunting is [semi] privatized. Enter Monster Hunter International (MHI)!
This was first introduced to me as ‘pulp fantasy’. Not all plots need to be complex. Not all worlds need to be rich and fancy. Sometimes the solution is as simplistically elegant as picking up a gun and shooting a monster in the head. The author describes this as “a conglomeration of B-Movie stereotypes but tackled from the perspective tactical realism” and it’s just that.
Lots of monsters, lots of guns, lots of shooting. That's it. Popcorn fantasy! I liked it.