I don't know if there will be NTR, but there are clues that LI may be engaging in sexual acts with other males or girls, not necessarily NTR, although often any scene where there is no MC is considered to be NTR .
However, the author does not allow himself to be conditioned by certain threats between the lines, because he has found an interesting and original narrative inspiration, while in other games we participate in the corruption of the family, in this game we have already corrupted the family, it is like play the sequel to FILF, MILF City etc. It may be interesting to see how the family is reduced now after we have corrupted it.
We have some clues, the brunette sister in depression (I think the imaginary boyfriend is the MC), the blonde who hates him (And I think she will have to do with the criminal he meets at the mall, I have no clues, is more an intuition, maybe the sister was going out or going out with the boss?) and the mother who by now corrupt could have ended up being the stripper (Maybe here is the alert for a real NTR, the mother seems to me to be a dominant woman and could force the MC to watch her have sex with others, or simply force him to attend a show by leveraging the guilt of the new MC).
Finally the EX girlfriend, she too has been corrupted as we see from the flashback, the way she behaves I find it suspicious, she could have another boyfriend now.
In conclusion, the ideas for the NTR (even if in reality it is not true NTR, since they would all be lawful acts) are there, so it is possible that there will be, if you do not feel like supporting it, simply wait to decide.
