Yeah - I also don't get it. This game is fully marked as a NTS game, and as such has the core of the MC's girlfriend having a good time with someone else than the MC and teases him with that. This is all because the MC is turned on by this, nothing more, nothing less.The double standards here is something simply amazing. Imagine the backlash if ntr fans went around asking the devs to waste time and effort adding ntr routes to vanilla games. Yet, that is exactly what is happening here, only in reverse.
What is also the very core of NTS, is that despite the girlfriend having a hell of a good time with someone else than the MC, she will never ever put someone else above the MC and will never leave the MC for someone else. She feeds the fetish of the MC and that's it. For her the MC is the most important person in her life and the one she truly loves, and the same goes for the MC the other way around.
In short - There are two things that simply do not belong in a NTS game, and that is a pure vanilla route where the girlfriend has no sex or anything but with the MC, or NTR where the girlfriend leaves the MC for someone else, or prefers someone else above the MC.
So yeah - If someone wants vanilla there are some games that have that over here (although there are a LOT of rape, hypnosis, violence, blackmail, SM, forced prostitution, torture, mind break, being drugged and other "funny" games that cannot be considered vanilla over here, so finding a real vanilla game can be actually difficult). And if someone want NTR - Well, there are several of them released (or updated) every single day, so not shortage at all. NTS at the other hand....