If the ongoing purge of incest games hits this project there is an easy way to remove incest. A character gained from the portal do not need to be related to the pair that fucked to summon them. Only the Infusion has explicit pregnancy, that makes it much easier to ban incest completely without too much of an impact.
Version 0.40 allows incest between siblings and between grand-parents/children. Fully preventing incest would be much easier if the only family bonds are between specific characters and their direct children.