I read the posts you linked, and they support what I and RC-1138 Boss said. There's also these posts to prove it.
ONE
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For now I'm at the bestiality will have to go and I'm trying to see how I can change the Myriam/Marc relation, but as of now, any family link, blood or not, is impossible, so my last attempt is "friend of the family" with Katherine being her daughter (so there will be no incest in the future with her) and Marc as Anthony's son, with Anthony and Myriam not being married. All this would mean some rewrite which could make me a bit late for my update this month.
TWO
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The main character is Myriam, every other character serve in the game as a tool to explore a side of Myriam or kinks in general, Katherine purpose is to explore the motherhood side of Myriam and also have a parallel with her own teenagers years and discovery of sexuality.
THREE
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Nothing changed with Myriam/Katherine, they were never meant to hooks up like with Marc, the only possibilities between them will come from some eventual triangular relationships.
Each secondary character is meant to develop/explore a side or kink of Myriam, Myriam and Katherine is really here for the motherly side of Myriam and the parallel to her own teenager years.
FOUR
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If there will be some potential naughty scenes or moment with Eve (like in first update of chapter 3) or with Katherine (potential triangular relationship with William), but no pure incest road with them.
FIVE
- For Katherine it will all depend of her orientation, she will have a few possibilities between men and women,
with Myriam being an influence towards who she'll go, man or woman (depending on orientation).
There's more like that, but they all either categorically state or reinforce that there will be no incest between Katherine and Myriam, and there was never going to be.
So, once more with feeling...
YOU'RE WRONG!!!!!!!!