>>58739295It's normal to feel sexual attraction to people who are genetically similar to you. However, if you fuck your siblings you'll produce retard babies from recessive gene expression. Evolution had to come up with something to stop you from doing this.
The end result is called the Westermarck Effect. This is the idea that members of the opposite sex that you grow up with are considered ineligible mates. The reason it's believed to be "those who you grew up with" is that they did studies on African villages where children lived communally and found they would find partners in other villages when growing into puberty. Additionally, there's examples of siblings who were separated at birth and reunited later in life who then found each other attractive.
