I think this is more common that we are told. We wouldn't want nature to take it course would we? It is better man made rules and laws to tell us how to act/behave. then someone else is happy having exerted their version of what is right!Years ago, when my wife and I were dating and even the first couple years we were married I had some hot Cumming fantasies about my dad fucking her. I just think it is so natural for a lot of dads to think sexually thoughts about their son's cute young GF or their daughter-n-law. My GF then wife would be sucking me off and I would cum so hard thinking I was my dad she was sucking off.