I work for my best friend, Joseph, at his web design company. It had been a long 3 months of 14-hour days, when he offered to spring for a trip to the coast for the long weekend. A few weeks earlier, he and my sister, Jennifer, had started seeing each other so she was coming, along with my wife, Sarah.
We were young, energetic, and fun. Staying at the secluded cabin my family owns on the coast gave us an opportunity to really let our hair down and go wild. Each of us would sneak off on occasion with our significant other to fool around in the woods or the bathroom or the car.
My wife and I, married for just 6 months, were fucking every chance we got. Every moment we were alone we were touching each other's erogenous zones, flashing our naughty bits at each other, kissing, sucking, licking. We fully managed 3 quickies and a blowjob one day. I was sure my sister and Joseph were doing the same.
The second morning after we arrived, we packed our daypacks with lunch, swimsuits, and towels and went hiking. It was about a half hour drive to the trailhead so right after breakfast, we piled into the rented Pathfinder and headed out.
Half an hour into the hike, Sarah caught up with me several paces ahead of the others and grabbed onto my arm. "Jennifer isn't wearing panties," she whispered into my ear. "When she was getting her pack out of the back, she flipped her skirt up to show Joseph when she thought I wasn't looking."
My sister and Sarah dressed almost identically today and their builds were so similar that people often mistook them for sisters: firm B to C cup breasts, thin waist, firm, athletic butt. So the image of her with no panties under her sports skirt leaped easily into my mind. A look of discomfort flashed across my face and Sarah, noticing, jumped in front of me, walking backward and flipped her own skirt up to reveal her trim little bush, unfettered by panties as a distraction. It worked.
"I can't wait for our turn," I growled.
It was about 20 minutes before they caught up with us again, and we stopped for lunch about an hour later.
Our hike continued along the rocky cliffs of the coast and Sarah and I allowed ourselves to fall behind. Once they were far enough ahead, Sarah shot me a flirtatious glance, flipping her skirt up to reveal her bare ass. We veered off to the side of the trail far enough that I could pull out my hardening cock and dip it into her slippery pussy as she bent over slightly at the waist and leaned against a tree. A minute and 20 seconds of rapid pumping and I unloaded into her with a triumphant howl.
We composed ourselves and began walking again only to realize what a mistake coming inside of her was when my large deposit began to drip slowly from her amazingly tight and panty-less cunt and continued soaking her inner thighs for the next 15 minutes of our hike.
Sarah and I had been trying to conceive a child since we got married, but were having trouble. Apparently the tightness of her vagina, coupled with an oddly angled cervix, held my semen securely inside her, but also prevented the sperm from swimming into her uterus. It was great when we were dating and would occasionally get careless, but now it was a curse.
This weekend was a good and fertile time for us to attempt to get pregnant. Since her period was a couple of weeks off, it afforded her the freedom to go without panties. I figured my sister was in the same condition since, until we got married, she and my wife had been roommates and had somehow regulated each other to the exact same menstrual cycle. Her reported lack of panties on this hike confirmed that for me.
Watching Sarah occasionally squat and dab a towel between her legs was an incredible turn on for me and I remained partially hard for quite a while, but I think my sister had caught her doing it a couple of times and may have noticed the bulge in my shorts because she was quiet or blushing for most of the remainder of the hike. By the time we got back to the cabin, the sun had set and darkness was rapidly approaching.
We made dinner and built a fire on the beach. After we'd had several drinks the conversation became loud and fun, but we were all so tired and ready to go to bed.
"Ok, everyone. I'm going to bed," Sarah announced, standing up. Leaning close to my ear, however, she whispered "I want you to fuck me under your sister's bedroom window. Meet me there in five minutes."
Yes, we were free to fuck in our room any time, but it was so much more fun to sneak clandestine romps outside of the approved frolicking zone. Sarah was a grand exhibitionist and never seemed to mind putting on a show or fucking in a place where we might get caught. She even liked to bring friends of hers home to watch us on occasion.
I stood up right after her with a similar announcement and followed her in. she went to the bathroom and closed the door and I went to our room. I heard Jennifer and Joseph come in and go into their room next door to ours as I listened to Sarah in the bathroom. After at least five minutes I decided to hurry her up a little. I walked down the hallway and heard the movement of the bed in my sister's room so assumed it was safe to molest Sarah in the bathroom, knowing she'd love the risks of doing it right outside my sister's bedroom door.
It was a turn on for me as well, as long as we were quiet. Actually getting caught in the act by my sister would be a major showstopper, probably for the rest of our stay. Stopping outside the bathroom, I reached my hand in and turned off the light. Sarah was standing at the sink and started to whisper something to me as I walked in through the darkness, but I made a quiet 'ssshhh' sound and put my arms around her, clasping her breasts through her shirt.
A moan escaped her lips and I ran my hands down her stomach, lightly tracing her curves with my fingertips. Her breathing quickened and I drew little circles on her tummy with my fingernails. I kissed the back of her neck, then took her earlobe between my lips and sucked. Bringing my hands back to her breasts, I squeezed and kneaded them while I pulled her body closer to me. She was really getting into it and so was I. I felt her press her ass into my groin and I reflexively pushed my hardening cock back against her.
Feeling my cock so hard, she reached down and lifted up her skirt, hooked her thumbs around the waistband of her panties, and pulled them down to her knees. Once she was bent over the sink, I put my right hand on her back to hold her there and used my other hand to push my shorts down past my fully erect cock.
She reached her hand back between her legs to grab my cock and then guided it to her slick wet slit. A few short strokes and I was deep inside of her. She reached down between her legs and started stroking her clit. This was a little unusual since she could generally come just by rubbing her thighs together and her clit was usually too sensitive for direct stimulation, but god damn it turned me on.
I was pumping her pussy as fast and hard as I could and soon she was writhing and bucking against me. She stifled a scream and stiffened as her body began to shake uncontrollably. Leaning back, she put her hand on the back of my neck and pulled me forward, locking her lips on mine.
"Your turn," she whispered as she leaned down on the sink, supporting herself with her elbows and silently gave me the go ahead to let my seed fill her belly. Maybe this time we'd get lucky and make a baby together. The thought of impregnating her turned me on immensely and I quickened my pace.
A minute later, I pulled her ass, by her thin little waist, tightly against my groin as I quietly moaned and stiffened, driving my cock so firmly and deeply into her I thought it would penetrate her uterus itself.
As I felt my cock come in contact with her cervix, I spasmed and let loose orgasmic spurt after spurt of thick potent semen. Imagining thousands of little sperm racing out of the tip of my cock toward that trophy awaiting them in her ovaries, I moaned in self-congratulation.
My cock still jerking, I leaned down and kissed her on the back of her shoulder. Just then I heard my sister's voice quietly, but a little panicked, asking, "Did you just come?"
Startled, I pulled back and out of Sarah's steaming cunt, jerked my shorts up over my cock and stepped back. "I'm not on the pill Joseph! I told you that!" she said.
Where was she? And why did she sound so close? Sarah hit me on the chest and I suddenly realized that she was speaking with my sister's voice. The door closed and the light came on.
Staring me in the face, skirt up to her waist and panties around her knees was my sister looking just as startled, and freshly fucked, as I was. "Oh my god!" she screamed in a whisper. "I thought you were Joseph!"
"Oh fuck! I thought you were Jennifer!" I whispered loudly.
"Jimmy, we just fucked! And I'm not protected!" she hurriedly sat down on the toilet and tried to push my semen out of her pussy.
"Can you wash it out? Like with a douche or something?" I asked.
"I'll try, but get out of here before we get caught." I turned off the light and opened the door again, hurrying down the hall to my room. Realizing Sarah wasn't there, another wave of panic washed over me and I hurried outside to our agreed meeting place.
