Matt stopped the car in front of the house where over a dozen teenagers were waiting for someone to pick them up and take them home. He looked around, searching for his sister Kate and her friend Jen.
It was not really a difficult search. Kate and Jen were definitely two of the most beautiful girls in the crowd, at least according to Matt. Kate, his sister was about 5'5" and had that healthy figure that you get if you exercise a lot, but you also like to eat pancakes occasionally. She had shoulder length brown hair that framed a face that was called sweet by her friends, with a pointy nose and bright green eyes. Jen was slightly taller and slimmer and had smaller tits, but otherwise the two girls could easily pass as sisters.
"I'm so sorry, bro," Kate said, when they finally found each other.
"It's OK sis," Matt said with a tired smile. "It's not your fault the party was cancelled."
Matt was right, but Kate felt still sorry for him. Matt had worked hard all day on a construction site and now he was here, giving her and her friend Jen a lift after a failed party. The fact that the party got cancelled because there was an explosion on a nearby construction site and all electricity, gas and running water was cut in the neighborhood for safety reasons did little to ease Kate's discomfort.
And part of this discomfort was that this was not exactly a party about which she would tell the truth to most of her friends. Or to her parents to be honest. It was a party organized by one of Jen's college friends to bring together new girls with boys to dance, maybe drink and have some preferably carnal fun. When Jen got invited, she asked Kate to join her, as Jen was notorious for losing her control around guys and she needed Kate to prevent her from doing something too wild she might regret later. This also meant that she and Jen could have probably ended up having sex with one or two guys together.
What Jen (or Kate for that matter) didn't know when she invited Kate to the party about a month ago was that the relationship between Kate and Matt would change radically a week later during a rather adventurous hiking trip into the Smoky Mountains, where the two teenagers got lost, soaked by rain and found shelter - and each other - in a cave. Kate was about to cancel, but Matt told her that it was important to keep their relationship in secret at this point. Also he was not exactly a jealous type, especially since they were still figuring out whether it was being siblings with benefits or something entirely different.
"Now ladies, please get into the car, so we can get going," Matt said. "I still have to drive you home, and that'll take about an hour even at so late in the evening."
"Or maybe you could sit on the back seat with me and Kate could drive us home," Jen remarked with a mischievous glint in her eyes.
"What do you mean?" Matt asked with some surprise in his voice. He immediately suspected what the little nymph wanted, but he never expected her to actually suggest it, and it immediately rang the "what about Kate" bells in his ears. A few weeks ago such a suggestion would have been Matt's dream, but now he was not so sure about that.
"Well, we came to this party to meet some good looking guys and have fun. And you are definitely a good looking guy..."
"Jen, stop it!" Kate interrupted. "I don't like where this is going."
"Why? He is tired and wants to relax, I'm horny and could use a nice cock. I'm pretty sure he would appreciate a little TLC on the back seat."
"You really want to have sex with my brother on the back seat while I'm driving?"
Actually this was a stupid question. Kate knew that Jen wanted to have sex with Matt ever since she had first met him, but Matt had a girlfriend at that time. Jen was not shy about such things and told Kate on more than one occasions what she would do to his brother. And although Kate would have never admitted it at that time, her pussy got wet and aching every time Jen did that.
"I know that you would like to participate, but someone has to drive," Jen smiled wildly.
"Jen, he is my brother," Kate protested.
"Oh come on, don't tell me that you two haven't fucked in that luxury bed of yours several times," Jen said. "You are a gorgeous girl, Kate and he is a fine specimen too."
Kate knew that Jen would never have any problem if she would found out that Kate and her brother were indeed lovers. As long as it was about great sex, Jen really couldn't care less who the partner was. Still, the siblings were not really ready to give up their greatest secret yet.
Matt took a deep breath, but Kate answered quickly, without blinking, "well, if you have to know, he never did."
Again this was actually true. Matt had fucked her several times with her recumbent on the kitchen table or bent over the washing machine in the basement, once even on the swing in the backyard, but never actually in her bed.
"Yeah, sure," Jen mumbled. "Anyway, let Matt decide," Jen said and she cast her sluttiest look on the teenage boy.
Matt looked at his sister. Although he considered Jen to be really hot, even four weeks ago he would have asked his sister first. Jen and Kate were BFFs and he was not sure whether her sister's BFF was free game. Kate saw the question in her brother's eyes and knew that she should react just as Matt had reacted when she told him about the party. She sighed.
"Well, it would be just evil to deny you two to have some fun," she said finally, as she grabbed the keys from her brother. "After all, getting some was the plan. Now get into that car and let's get going."
Jen and Matt sat onto the back seat and Kate sat behind the wheel, ready to drive them home. But before she started the engine, she quickly adjusted the mirror to be able to see what was going on behind her.
"Someone is curious about what will happen to her little brother," Jen snickered. "OK princess, you may watch."
By the time the car got out of the street, Matt's pants were at his knees and Jen's tongue was hungrily running along the length of his rock hard cock, occasionally kissing its tip. Matt let out a content sigh and sank into the back seat. He put his hands on Jen's head and gently dragged her closer to his cock. She took this as an encouragement and took it into her mouth. Matt searched for the rim of Jen's panties and when he found it, he slipped his free hand inside and began massaging first her outer lips, then her clit, occasionally venturing a bit more inside to gather some of her fluids.
Kate occasionally cast a glance through the mirror at the erotic scene that got wilder by the moment behind her. She hoped that her friend would not suck Matt completely dry as she had some plans of her own, provided that Matt had any energy left. Her hands occasionally travelled to her own wet mound, but she did not dare to play with herself as she was afraid of losing control over the car.
On the backseat things were heating up. Jen had to stop sucking Matt's shaft as she could only concentrate on Matt's professional play on her clit. But she did not want to cum from his fingers, she wanted to cum on his cock and feel as he pumped her pussy full with his cum.
So Jen raised herself over Matt's lap and pulled her panties sideways as she did so. She positioned Matt's cock to the entry of her wet pussy and was about to lower herself when Kate accidentally hit a pothole and Jen unceremoniously impaled herself over Matt's rigid member. Both Matt and Jen let out a deep, peremptory growl.
"Oh, sorry you two," Kate tried to apologize on her cutest voice, but neither Matt nor Jen listened.
Both of them have been teasing the other for several minutes by that time and this sudden, hard impact overwhelmed their senses and now reaching an orgasm became first priority for both of them. Matt grabbed Jen's ass and started to pump her really hard. So hard that Jen had to put her hands against the headliner to seek support.
"Fuck Kate, he's a real machine," Jen panted. "With a supercharged piston."
