Monster Girl Dreams

From the introduction:

Lucidia, an entire continent of beautiful vistas, labyrinth dungeons full of treasure, and monster girls chomping at the bit to get their hands on a man. You, a graduate from adventuring school, have arrived in this den of darkness to prove your worth, free yourself of debt, and maybe defeat the Demon Queen. There’s only one problem: physical violence is impossible anywhere in Lucidia, meaning you must get ‘physical’ with the monster girls in a different way to defeat them.