>>8695389
Closed Game (https://vndb.org/v16700) might be what you're looking for. It's mostly a Hunger Games kind of parody story, so you won't see much of any content outside of that idea. It was officially translated years ago.

I'm looking for more adventure fantasy NTR games, especially one's that have vanilla content/routes to them. The NTR is much sweeter if there's vanilla filler in-between to establish relationships before the fall. Dungeon of Regalias (https://vndb.org/v18761#main) has vanilla content and NTR bad endings for each girl. There's also Demonion (https://vndb.org/v10041), where the player in certain circumstances can initiate an NTR flag where the MC's his obsessed maids trick any of the heroines you were going for into a situation where they get raped by monsters and turned into breeding stock. I'm basically looking for anything where you can play as a medieval hero or at least has someone for that role in the story, but he can get NTR'd.