Not bad. This game is good, although its incompleteness is...mildly frustrating. I'm not complaining, the fact that this left me wanting more NOW is a sign that I like it.
Graphics are more than decent, though nowhere near the quality of a masterpiece like Cyberslayers (don't try it dev, that's hell you're looking at).
Right, well, let's move on to the 'areas of improvement'.
Let's start with the obvious. This...isn't NTR. It's closer to cheating turned swinging.
NTR must have an intellectual or moral aspect, showing us how the girl is changing and/or being corrupted (e.g. bimbos losing their intelligence and powers of judgement would be an intellectual aspect; a wife losing her love for her husband and family and changing how the entire family unit works would be a moral aspect).
Here, Aki's change is entirely superficial. Without helpers like fluctuating sex stats, we have to rely on what's shown, and what I see is the shallowest of changes. To test the NTR, I try to see if I can explain the actions of the characters without going into NTR territory, and it's laughably easy for Aki--she's basically doping on demon seed, and her change is entirely explainable by that because the story never tells or shows us otherwise. She's being drugged, not slept or loved away from her husband.
Adding to that is how the player has very little agency. There's only ONE choice so far, and I don't know how much it matters. In other words, this would've been better as a Renpy game--it saves time and we get the same experience. It's not a dealbreaker like Lily (playing that on Renpy vs RPGM was two vastly different experiences, and Renpy was far superior), but I think some dialogue choices would at least be more helpful in making this fit its medium.
-I mean, the core gameplay of this particular RPG is clearly character-building: making your character fit a role, a role that you are playing, as it were. Some actual choice would be welcome.
Finally, chapter 4.5 was a little bit of a disappointment. With how Aki stimulated her lover I was expecting something like them falling in love with each other. But the fact that her nature as a sex demon overpowers the affection is...well, I want some real character development, is what I'm saying. Aki becoming her main girl would be very gratifying.
PS: I would also appreciate it if actual cuck scenes were included--the dev knows what I'm talking about, he did one with the bunny boy and his girlfriend going to that orc or whatever. Aki doing this with increasing severity to Jake could serve as effective milestones of showing her fall.