It's an entirely subjective line, and depends on context usually.
It's probably a lot easier for The Witcher 3 to have a couple of scenes like that since it's not the main focus of the game. The Huniepop stuff is a lot more transparent.
I mean I can totally get it, but then the question is what about visual novels who just have 3-4 sex scenes in 30h "reading", which are still censored?
What about games that dont even have any sex when they arent patched?
What about "loli characters" in fighting games wearing skimpy outfits and be seductive?
Some have some fanservice scenes.