This game isn't ridiculous, this is how NTR works. Aiden's perspective exists just to take L's so that Luna gets corrupted and you get to watch the process over every single update. That's how NTR stories work in 99% of cases and this game is no different. It never has presented itself alternatively, the dev's previous games work like this, it's real simple.
There's also the writing keeping Aiden in perma-cuckold state with the disease that keeps him permanently weak and pathetic. He wasn't before, but the instant-cuck plot disease is not going away anytime soon. Which keeps Luna also compromising herself too, up until the corruption breaks her. Which, again, is the whole point of this game and NTR as a genre.
Aiden/protagnist is not supposed to win. The most common ending I've seen in NTR games is transitioning to NTS after the protag finds out and realizes they're into being cuckolded. That's a best-case scenario, other popular ones involve protag finding out and: mind breaking, emotional breakdown, breaking up, getting pegged, finding another girl that also gets corrupted for cuckoldry x2, killing one or both people and going to jail, etc. What do all those endings have in common? Protag takes an L.
I think what you're after is swinging and/or cheating genre's. NTR has aspects of those genre's, but what is playing out in this game is exactly what NTR is about: one-sided cheating / hidden sex / corruption build-up / one bull / one cuck. Hell, the inclusion of Nevin is providing that alternative so there's more than just Vargas and Luna events happening.
I hope that helps and you find the kind of game you're looking for. Because Aiden is not getting a W in this game, ever. Which is what everyone else here is for.