Goblin Layer (in development), Paccsu (complete), and Princess & Conquest (in development but lots of content) come to mind, but they are RPG maker games. I personally thought they are all well made despite that. If you want something more dependent on the mods you put into it there is always Brothel King. All characters added can be custom made by yourself or other players. It's just images though and sometimes (although rarely) gifs and videos.