There are perfectly understandable English tags available for this game. I've said this a zillion times elsewhere, but I'd love to see "NTR" prohibited as a tag and force people to either identify the specific subgenre(s) or use English terms. The prevailing belief behind "is NTR avoidable?" inquiries is that any form of extracurricular sexual activity is NTR, and of course that's completely wrong.
So here we have a game based on rampant and unavoidable non-monogamous sex. Unavoidable for the wife, at least. Avoidable for the husband, if one wishes to play that way. The only instances of netorare are with Martin (who could just as easily receive a cheating tag, plus a jealousy or willing/unwilling cuckolding tag if it existed), Ryan (ditto), and the husband/spa dude whose name I suddenly can't remember, though even then the only hint of netorare was when Anne gave him her panties at dinner and didn't tell her husband about it until later. We don't actually need Japanese terms for this game and we don't really need to be discussing them. Yet we are.
Ultimately, this isn't an NTR game and would never satisfy players for whom that's their fetish. It could eventually become one if it goes on long enough and the player makes a certain set of choices, but right now it's a willing cuckold/open relationship/hotwifing game with the occasional nod towards swinging or very occasional netorare. That this discussion exists in this thread in the first place is only because people don't understand what NTR is and isn't. We obviously don't want to have a discussion about that because it'll just get deleted, but it's not because there aren't better ways to tag the game. There are.