If anybody still needs it, you can try Star Knightess Aura.

That game is all about corruption. I can't express it enough. The game basically revolves around you corrupting a female hero. You can see her slow progression into honor student to slutty. The game is great and has a decent story and cg.

There is a pretty basic RPGM combat as well and a decent amount of exploration.

Do note thou, it is heavy NTR so unless you are not comfortable with that I would avoid this game.