Call me crazy but... It would be possible to make a patch so that this is "NTR"? That is, simply changing some dialogues... Or maybe adding some where the MC tells Yuka that he likes her and they are dating or something like that... After breaking the first fragment maybe... And hints could be added of this in some events... For example in the first one of the "forced kiss" in the forest you could add a dialogue of Yuka "thinking" and saying "why didn't I stop him? Even though Satobito is my boyfriend..." I don't know, to really give that sense of NTR to the game, you know? As a separate mod. I would do it but I don't know how to use RPGM