This is the third chapter of the Chemistry series. You may want to read Chemistry 101 and Chemistry 102 before you enjoy this one.
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Sarah's heart was pounding in her chest, thumping against her ribcage as she finished gathering her belongings from her locker. Even though she had already enjoyed a vigorous fucking during second period, she had been dripping wet all day. The knowledge that she was one careless move away from flashing her swollen cunt or her hardened nipples to her classmates was utterly titillating. Sarah was beginning to think she might be a bit of a closet exhibitionist - getting finger fucked in the back of the lab with only a table to block the view had been even hotter than she'd imagined. Not as hot as going down on Nate while Rob slammed into her from behind over that same lab table, but still really, really hot.
Sarah felt moisture begin to slide down her inner thighs as she pictured the three of them fucking in the study room where Nate's fingers and tongue had brought her to such an intense orgasm the day before. She leaned her forehead against the cool metal of her locker door, breathing shallowly as she fantasized.
Suddenly she was pinned against the locker by two hard, male bodies. A low voice whispered into her ear, warm breath on her neck.
"Hey there, little girl. Did you miss us?"
Sarah spun around, turning to face the two boys who had been driving her to distraction. Nate and Rob leaned into her, demonstrating quite plainly that they too were already turned on. Two stiff cocks pressed against her hips, making her lick her lips with anticipation.
Nate, consistently the bolder and more mischievous of the two, reached up under her skirt, swirling his fingers against her clit before sliding two fingers into her wet, eager cunt.
"Damn, Sarah. Have you been this wet all day?"
She looked at him with widened grey-blue eyes shining with innocence.
"Am I wet? Gee, I guess I am. It must have something to do with the fact that I've been thinking all day about the two of you fucking me until I can barely walk."
Rob made a low, strained sound in his throat as he jerked his cock against her hip.
"God Sarah, it is so fucking hot when you say things like that."
Nate thrust his fingers slowly in and out of her, not breaking eye contact for even a second, as he said, "Well, I guess we'll just have to move this somewhere more private." He withdrew his hand from her cunt, making her whimper slightly. Still holding her gaze with his own, he sucked his fingers clean, before remarking, "You taste fantastic, by the way."
Her knees trembled beneath her, but she managed to remain perched atop her four-inch heels, supported by the pressure of their hips against hers and the hard metal lockers at her back. She gave them a slow, sultry smile.
"All right, boys, where to?"
Rob and Nate glanced at each other. After a moment, Rob said, "My parents are out of town for the weekend. I have the house to myself for the next two days."
"Perfect," Sarah replied. "By the way, you guys are clean, right?"
They both nodded.
"Good, that means we can dispense with the condoms - I'm on the pill."
Huge grins appeared on their faces.
"All right," Rob announced, "I'll drive."
Sarah wasn't sure how they had made it to Rob's pickup truck, barely keeping their hands off of one another. She clutched the strap of her shoulder bag with both fists, fighting to maintain enough composure to give the outward impression of calm.
Rob opened the door for her, and she hopped up into the truck, sliding across the seat to the middle of the cab. Nate jumped in beside her on the passenger's side, and Rob slid into the driver's seat. They closed the doors with a thud, and Rob turned the key and threw the truck into drive. As they peeled out of the parking lot, Sarah dropped her bag and jacket to the floor and breathed a sigh of relief.
Her brief moment of calm lasted about three seconds before Nate grabbed her about the waist and pulled her into his lap. He clasped her shoulders in his large hands and kissed her passionately. She thrust her tongue into his mouth and ground her bare cunt against his lap, reveling in the friction against her clit.
Rob groaned and clutched the steering wheel with both hands. He pressed harder on the accelerator, urging the truck faster along the road.
Nate reached between them and scrambled to unbuckle his belt, jerking his pants down over his hips and down his thighs a few inches. Sarah rose on her knees briefly to readjust her position over his thighs, then sank down onto his cock. They both moaned.
Rob turned the car onto the gravel road that led to his house. It was uneven, and the truck was old, with lousy shocks.
Sarah bounced up and down on Nate's cock with the rhythm of the truck's movement. She clung to his shoulders and kissed him, her tongue dueling with his.
"Oh my God, you feel incredible," he gasped into her mouth.
Nate brought his hands up to her breasts and squeezed, circling his thumbs against her nipples through the thin fabric of her tank top.
Sensing that Rob was feeling left out, Sarah reached one hand out to the side and stroked the bulge that pressed against the fabric of his pants. He involuntarily thrust his hips against her hand, causing the truck to jerk forward as he pressed harder against the gas pedal.
"If you keep that up, I'll have to pull over," he warned.
"Fine, fine," she laughed, "I'll keep my hands to myself and Nate over here."
Nate moved his mouth to the side of her neck and began kissing her pulse point, laving it with his tongue. She arched her back and pressed her breasts into his hands, lifting her hips up and down, squeezing his cock with the tightness of her cunt with every motion.
Suddenly they came to an abrupt halt. Sarah bounced particularly hard against Nate's lap, his rigid length penetrating her even deeper than it had before. She moaned.
"We're here!" exclaimed Rob cheerfully, "Time to get out!"
Sarah leaned her forehead against Nate's and sighed. He thrust into her few more times, then reluctantly withdrew and allowed her to dismount. Rob helped her down from the truck, slamming the door shut behind her. Nate followed a few steps behind them as they walked up to the house, his gait somewhat awkward due the bulging erection he had stuffed into his pants.
Rob opened the door to the house and escorted Sarah to the kitchen, Nate trailing them.
"You want anything to drink?" he offered.