Opal stood there watching my son, Alan, slam his fat 8 inch cock into me from behind. I was in the throes of too many orgasms and too far gone to care what she, or anyone else for that matter, cared.
But rather than being outraged, Opal was turned on.
"God that's the sexiest thing I've ever seen," she said as she lifted her nightgown over her head. "Keep fucking her, I'm so turned on I can't stand it."
As I looked over, Opal was completely naked, had two fingers in her pussy and her other hand was busy squeezing a nipple.
Never a quiet lover, I was moaning and thrashing about. "Slam it into me, Alan. Fuck me. Don't stop. I want your cock."
Up on my knees, Alan held me by my thighs and kept slamming into me over and over. Then, suddenly, he slowed down. Pulling his dick almost all the way out, he slowly, agonizingly, pushed in and then pulled back out just as slowly. I could feel the entire length of his cock going back and forth and it was driving me crazy.
Just then, Opal climbed onto the bed and crawled underneath me. She stopped at my breasts and started licking one while squeezing the other.