The small hole in the middle of Lisa's cervix slowly opened up, as the neck of her uterus pressed against the tip of John's penis, until it slowly sli... down over the head of John's penis, and didn't stop until it had engulfed the entire head of his dick, and then some.Then her cervix tightened up around the shaft of his penis, and the muscles at the entrance of her vagina finally relaxed. The neck of her uterus started massaging the head of his penis by repeatedly squeezing it."Is my...penis. “So what would you like to do girls?”“Well, Linda was keen to do some revision for next week’s Biology exam”, said Sue.“Well I can’t help her there it isn’t a subject I have ever studied apart from in General Science exams and I dropped that two years ago.”We were all three sitting around the kitchen table and the girls looked at each other a little hesitatingly before Sue said “Well, you probably can. Linda has some questions about human reproduction and she thought you might be able to. . jerk Ron's cock with her panties!" Josie sighed, and then casually reached over to my hard member, wrapped in Katie's aqua blue panties, and taking hold of it, began to gently massage my cock.I instantly had to fight the urge to moan out loud, the thought of my hot blonde cousin jerking my hard member right there surrounded by our class mates and professor was amazing, and the fact I had Katie's knickers wrapped around my cock, was so hot as well.For about a minute my cousin stood beside me,. She will need a lot of foreplay and Ingrid is just the girl to do it. If she doesn’t get wet enough then Ingrid knows where I keep the lubricant. I want you to fuck her good…several times if you can…they are prepared to spend the night and most of tomorrow if necessary. They said that they can miss church for something this serious.”I was not allowed to have sex with either of them. We ate dinner and waited for their arrival.The old man looked very old, like someone’s great grandfather,.