What is incest?

Wouldn't it be cool to fuck your sibling? Maybe not to you, but **it is to me.**<br><br>I tried to let my little brother know that having incest is a great idea. He's right below me age-wise (I'm around 17). His answer was that incest leads to mutations and other offsprings' defects. So I started researching. <br><br>Now I know that incest is dangerous, and most of the time leads to defects in the offsprings. But I'm not sure if I believe it. Maybe that's just **Semantics.**<br><br><br>Edit: I'm not looking for help, because I know I have family feelings for my brother, so I'm not going to look for help, but I just wanted to know about incest.