Alright, I only played partway through the NTR path, but I can see how it's gonna go. I'd like to leave some constructive criticism.
There is an issue with this route on a conceptual level. You did not pick the target audience within the subset of NTR fans, nor did you keep a consistent approach to the MC's motivations and characterization. There are many different archetypes for the NTR protagonist. The oblivious fool, the beta weakling, the willing cuckold/netorase guy, the asshole that drives people away, etc. It's important to figure out what your MC's type is. It's not that you can't mix some of these types, but you need to do so intentionally and with purpose.
You are all over the place with the MC. You need to be understanding with the father to get his NTR points (beta). You need to be mean to the mom (asshole). You need to be an asshole to your sisters for absolutely no reason (asshole). But then, you need to encourage every family member to get a personal trainer and watch cuckold porn and stuff (willing cuck). All of a sudden, you are worried about the mom being used for the mafia sting operation thing (beta).
None of this is cohesive. It's just random stuff with no progression or consistency. The issue is exacerbated by having no NTR routes for the workplace. You need to choose between pure and dark, and I can't decide what fits the NTR MC more. If the MC was the classic beta or oblivious type, a pure route would fit thematically. If he was an "alpha cuck" who wants to corrupt the family by sharing them and shit, the dark route might fit. But the MC is neither this or that.
So that's about how far I got. It just doesn't work. Based on what I saw during the NTR route, I am pretty sure the Dark or Pure routes will not suffer this problem. They seem to have some consistency.
Overall, I think the game shows promise. There was no issues with grammar or dialogues. That's a big plus. The scenario could use some work, but the general idea seems decent. I would probably enjoy this one as a typical HTML power fantasy if I play the Dark route. NTR route needs a lot of work though. I don't know if it's feasible to address the issues I pointed out, but good luck regardless.
