Should probably not even bother including NTR. Based on the dev notes, there's gonna be so little of it in the game, that NTR fans won't really care for it, but any NTR, no matter how small, gives NTR haters aneurisms. If 95% of the game is harem/vanilla/non-NTR, might as well go full non-NTR.
But that's from the perspective of wanting to draw in fans. If that's simply how the dev envisioned the game, then more power to them. Make the game you want to make, regardless of how people feel about that three letter word (abbreviation?).