Honest Feedback:
1. The portraits when a character is talking are naked. I feel like it should be them with clothes, unless its an event where they are naked. They don't have to be specific to what clothes they are wearing at the given scene, but clothed vs not would be good in general.
2. Father is a bit meh at the start, I get walking around naked, but with an erection and being fine around the kid, then talking about the drugs. A little odd dialog, but not a big deal. Perhaps have him muttering to himself and the kid hears it, then looks into the drugs or something. (just my opinion on that)
3. Character designs are ok. I prefer a bit more realistic look, rather than everyone being super stacked and with giant asses, but that's a bit of a preference. Something like "Mirror Mine" has a more realistic looking parent. Although, having her being stacked is fine as well.
4. The description of the Mother and the other person is a bit odd. I'm not sure if that is information the character knows or if its just for us (First person vs third person omniscient)
5. It may take a bit of coding but I feel you have some kind of background for characters (which I like) but adding a character database would be cool. You can put the details of the person there. Since I'm not a coder / scripter I don't know how hard that is, so its not really a negative that it is lacking, more of a "it would be cool if"
Other than that, not too bad. I hope its a slow burn and less of a "mom saw my dick and now she can't help herself" trope. Something that follows the real struggle that would occur with feelings that violate such a hard line of "incest"
I look forward to seeing how the story grows. I hope its more of a slow burn between the mother and son.
I wish I could write for these games, but sadly I lack the CG skills to have various characters shown.