It's simple. Incest is just not in line with the moral fabric of society and the positive values of the 'Harry Potter' series. The books are about things like friendship, loyalty, and good vs. evil, not inappropriate relationships.
In whole family incest stories, you might find themes like psychological trauma, the struggle with forbidden desires, and the impact on family relationships. However, it's important to note that such topics are highly controversial and inappropriate.
Well, first of all, incest has no place in the 'Harry Potter' world. J.K. Rowling created a magical universe based on positive values. Incestuous ideas go against the spirit of the original work. Instead of thinking about such inappropriate ideas, we can focus on exploring the wonderful magic, the growth of characters, and the complex relationships that are already presented in a proper way in the series. For example, the friendship between Harry, Ron and Hermione is a great aspect to delve deeper into in fanfic.
I have a novel here that suits your needs. It's called " The Twin of the Dragon Ball ". The main character and Kakarot are twins. They only have one wife and are even together with their childhood sweetheart. However, there were also some scenes that hurt other little friends, but not too much. I hope you will like this novel.
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