Mhh I think NTR in this game mostly stands for
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. So the MC steals the girls from the antagonists. So his plan e.g. is to steal Melanie from Mark (her husband). In the beginning you also see some sexual scenes between Mark and Melanie but its rather vanilla and the MC controls Melanie in a certain way while doing that. Have a look for yourself.
If we would change the perspective and Mark would be the MC then it would be
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. If the perspective would be out of Melanie's POV then it would be cheating.
So whether its NTR always is a question of the perspective in the end.