So far, I don't think that
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is giving issues so far. But I warn you that unfortunely it isn't the only the subscription platform that gives issues, but the payment methods that do it. You can read
this comment since it explains a bit better than me, because I don't use Patreon at all. I also don't understand how it works, because Steam has games like
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, and it has incest, although not mother and sister. So I have no idea.
Finally, if you want to play it a bit safer, you can use a side patch for it. Some games have the coding inside, with the patch changing a value from 0 to 1 to enable it. Personally I think it's dumb, since it's fantasy anyway, but whatever. Many games have assassinations, genocides, war crimes, etc, and that doesn't mean it is a good think to do irl.
the VN game I'm currently working on is about a family, and if the name family is in the title, I think its a dead giveaway of an Incest game.
You have my attention. Good luck on your project.