its pretty bad when monster rape just seems to become a running gag.
Free Step Dodge
Russian-chiropractic19
VAND1TA
its totally in my top 5 best manga every read!!!
Brute
I've never read it, but on principle it seems like one of the better ones simply for what seems to be a focus on world/narrative rather than pervy highschoolers.
Darkslay
You wouldn't last a volume of Violence Jack.