Repeat the experiment with different variables

You cradle Tommy's head against your hanging breasts as he licks around and over your stiff nipples. He sucks each in turn, squeezing your tits gently and teasing your hard pink buds without pinching.

"Mmmmm," you moan and squeeze his cock again with your pussy, "you're showing definite improvement."

His hands glide down your smooth back, over the ruffled schoolgirl skirt, and settle ony your bare ass. He squeezes and massages your ass and his fingers spread apart your cheeks. As he explores your firm butt Tommy continues to kiss your breasts and suck on your nipples.

The fondling and the gooey warmth of your pussy is enough to reawaken the geek's big prick. You feel it hardening within you and you coax it with gentle contractions of your muscles. Your mixed juices leak out of your pussy and down his balls.

"Are you ready for another round of testing?" You ask.

Tommy reluctantly pulls his mouth away from your nipple.

"Yes," he thrusts his cock up into you to underline his answer. "Could we try a different...?"

His words trail off as you begin to roll your hips and lift yourself up and down on his thick shaft.

"You want to fuck me," you pause to moan, "in a different position?"

You sit upright with your hands on his chest, your body rising and falling to meet Tommy's thrusts. Your large breasts sway up and down in perfect rhythm with his pistoning dick. You cry quietly with each upward thrust. Tommy stares at you for more than a minute before he can answer, lost in the pleasure of your steaming hot, sopping, and gripping cunt.

"I...yeah...," he finally manages. "I want to..."