I don't usually check out kinetic games, because the writing in any game of this type usually isn't very good. But MNG bucks this trend pretty consistently. Let me try to explain.
Years ago, a movie reviewing Youtube channel called Red Letter Media did a huge takedown of the Star Wars prequel trilogy. One of its most damning observations: Try to describe any major character in one sentence. You can probably think of a few things to say about each one if you are familiar with the films, right? So what's the big deal? Well, here's the thing: Do that same task with the major characters of the original trilogy. The difference in character depth reveals itself very quickly.
Each major character in MNG is multi-dimensional in this way. They each have distinctly different attitudes, appetites, and motivations. It makes them feel like real people, which makes it exciting every time they cross another boundary. You're watching someone evolve or at least reveal more layers of their identity.
For example, Violet is a saucy exhibitionist and teases the MC about doing stuff with other guys -- but she's ultimately loyal to him and says these things because she knows it excites him. The MC's older stepsister is unpredictable and dominant, but she's ultimately trying to bring her people out of their shells and get them to acknowledge their desires.
There's also a lot of foreshadowing and titillation along the way, done sometimes in inventive ways. It builds a lot of anticipation, and I can sense the creativity and careful planning happening behind the scenes.
Granted, the teasing-to-delivering ratio has remained strongly in favor of teasing. After a year of updates of a game whose description says that Violet "will follow a NTS route (sharing, swing, exhibitionism)", we've only really seen the exhibitionist side so far, and a bit of groping. The MC's own sexual interactions with people other than his girlfriend have been very minimal. The devs keep edging the audience, and just like in real life, there's a limit on how much of that you can deal with before you lose interest, walking away feeling like the promises were basically hollow all along. So for now, MNG is a five-star game for me, but they're really pushing it. There comes a point in the conversation where you have to stop flirting and make a decision.