I'm sorry bro... but just no. There is absolutely NO NTR in this game. There is Netorase (NTS/NTRS), but no netorare. Netorare is to be taken from in the tradational sense of the word. However, on here it doesn't need to be stealing of the LI, just cheating or for an LI to choose someone else besides the MC.
The character stops being a love interest the moment you avoid/decline her. The MC has no interest in that character, so she isn't being taken from him, and the MC would have no reason to be jealous either. So even the F95 definition of the word (which is a really bad definition and somewhat broad), doesn't even fit in this case.
I can understand why some people wouldn't like this content, but I never understood why so many people on here complain about avoidable/optional content. However, I wish the term NTR(netorare), would stop getting thrown around so much on here, it's used so loosely at this point that it's starting to lose meaning.