And what exactly would "similar" be? Because if "similar" would mean seeing other male characters fuck female characters that aren't even pursuable LIs or side chicks, then that is not similar to NTR.
For those who tried the "something more" and got rejected for being DIK affinity, even though they did everything with M&J and earned all their RP points, it is a bit of a kick in the teeth to see them kiss when his back is turned. Sure, they're a couple, but they just rejected the MC, so the least they could do is be a bit sensitive to that and wait until he leaves the room.