Title: Pain Killer (sometimes stylized as PainKiller)
The world is overrun with monsters and there is a group of warriors designated to clear the surface. Juan is one of these warriors. He travels to the surface to fight these creatures, and while many of the monsters do exclusively want to kill and eat these warriors, many also want to dominate them. These monsters crave more than the taste of human flesh, and though Juan tries his best to fight them off, he finds himself in the throes of passion with these creatures.
Of course, he shouldn't want it. He shouldn't enjoy it. But after he's rescued and integrated back into human society, can he ever forget the pleasure he experienced?