Mom catches son her panties.

Suggests that he play her part.

Mom blindfolds dad, suggests anal.

Dad takes son's virginity.

Next night, mom washes all hair off son's body.

Blindfolds dad again, introduces son as girl to play with.

Mom and son suck dad cock together.

Mom says, "what if she had a cock, would you like that?"

Dad says yes.

Son and dad 69, while mom watches.

 "What if she was your son? Would you want to fuck her like you fucked my ass?"

Dad says yes... then is convinced to switch.

"Which do you like better?" 

Dad likes both. Son unblidnfolds dad.

They both turn tables on mom, and fuck her, while kissing each other.