Ever since I can remember we had been taking family vacations around the country. We had a small RV that dad drove everywhere. We’ve been from coast to coast in that rig and been to some pretty amazing places. but the most amazing place I’ve ever been was on my last trip in the RV.

The RV was not very big. It was advertised as ‘Comfortable for a Family of Four’ when dad bought it. It had one standard sized bed for two in the back, hidden behind a door that folds out from the bulkhead. The other sleeping arrangement for two was a bunk that could be made by dropping the only table on the bench seats and lying the seat cushions on the flat surface. That’s where my sister and I slept when we traveled.

The first few years it didn’t bother me to sleep beside Madison in that cramped makeshift bed. Sometimes we would fight over space and blankets, snarling at each other through the night, other times we would laugh and giggle as we played innocently into the darkest hours until mom or dad would yell at us to shut up. About the time Madison turned entered puberty she started to protest loudly and often to our parents about the sleeping with me while we traveled. At first I didn’t understand but eventually I caught on. My hormones were beginning to rampage wild and free and I couldn’t help but notice that Madison had developed a fine-looking set of tits to complement a hot body. Even though she looked absolutely fantastic, she was my big sister so I started to complain about sharing the bed with her too.

The next two vacations Madison and I fought like the proverbial cat and dog. As long as it was daylight we got on civilly but when it came time to go to bed, I felt nothing but revulsion for her, my parents, the RV and the trip. We stopped putting on pajamas and slept in our clothes. I would take a blanket and wrap up like a moth in a cocoon, she did the same. We had layers of clothing and blankets insulating us from each other but many nights neither of us would sleep, too conscience of the other lying nearby.

As I grew older and my balls got bigger I became more aware of girls. There were girls in my school that could stiffen my prick with a glance. Hell, I got hard just imagining they glanced at me. I was learning to flirt with them and even had some success kissing some girls in my class. I knew what I wanted from them but I still hadn’t built up enough courage to make a pass at anyone. I was getting turned on hard, my nuts ached daily but my only sexual outlet was self-inflicted satisfaction in the lonely hours of the night.

By the time I was 16 and Madison 17, she was dating some smug looking super stud football star. I didn’t like him because he was one of those guys that could get any girl he wanted, any time. Why my sister hung with him I don’t know but she was gaga over him. I wasn’t dating anyone; most of my time was spent with my friends telling each other lies about how great we were with girls.

One early summer night I was walking home from a friend’s house, taking a shortcut across a field between two streets. Half way across I noticed a car parked under the large trees on the north side of the field. It was super stud’s car, the guy my sister was dating. The moon was about half full, bright enough that I could see the silhouette of him in the back seat necking with a girl; I assumed immediately that it was Madison who had her lips welded to his. Instinctively I ducked lower and crept closer to the car. I reached the blackest shadows under the nearest tree and stood in the dark, opposite the four wheeled love nest. The windows were open so and I could see and hear the two of them, they were so busy with each other they had no clue I was just a few feet away.

I could hear him talking trash, telling her how beautiful and sexy she was and she was wondering out loud if he really meant that or was he just trying to have sex with her. Super stud assured Madison that he loved her deeply and forever and was willing to prove it. I could see well enough that I watched his hands busy on my sister’s body. She wasn’t fighting for her virtue very hard and in a short time her blouse was open and her bra was pushed up to her neck while he was licking and kissing her tits with one of his hands under her skirt. I could hear Madison moaning quietly, cautioning him to go slow but it was obvious that she was heating up fast. As I watched the seduction of my sister, my own cock began to grow.

Stud and Madison wrestled and twisted around the seat as he pulled her panties off. I watched as she laid back and put one leg over the back of the seat, I guessed the other foot was on the floor; in that position she would be wide open between the thighs which is where he wanted to be. He managed to unbend enough to open his pants and pull them down. I caught a flash of his bare butt before he eased down on her. Not only was my cock solid, my balls were beginning to ache. I heard Madison tell him “You have to be careful, this is my first time and I don’t want to get pregnant.”

It took a few seconds to realize what I had just heard. My sister was giving up her virginity? I was witness to her first time? He grunted back at her “It’s okay, I’ll pull out before I finish.”

There was a pause, nothing but still air around the car then I heard Madison cry out “Ohh, Ow! Stop!”

He answered her protest with, “Shss – it only hurts for a little, you’re gonna like it from now on.”

It didn’t sound to me that she liked it; she simpered softly “Stop. It hurts, let me up.”

Madison didn’t say any more but he didn’t stop. I could hear his body slapping hers as he screwed her. A few minutes later he hissed “Aww that feels so fucking good” and went limp.

Madison wailed into the dark, “You said you would pull out! You didn’t pull out! What if I get pregnant?”

He looked down on her, “Shut the fuck up, you can’t get knocked up the first time.”

I was torn. I was excited because of the sex show but pissed at him because he unloaded in my sister after he told her he wouldn’t. The urgent need in my balls overcame the anger so I stepped back around the tree, pulled my dick out and began to jack my handle while the lovers rearranged their clothes.

About the time I sprayed the tree with my seed, I heard Madison ask him to drive her home. He shot back, “Why? You only live a couple of blocks from here, you can walk.” A door opened then slammed shut as I tucked my relaxing prick back behind the zipper. I peeked around the tree to see my sister running through the pale moonlight toward home. I stayed where I was, waiting, watching; I wanted to see what Stud was going to do.

As soon as Madison blended into the dark, he pulled out his smartphone and punched in a number. A short pause later I heard him say. “Hi, whacha doin? Can I come over, I got a little something for you?” Another pause, “Yeah, I was out with her but she don’t put out and I have a real need for a good fuck. Lemme come over and I’ll put my cock anywhere you want it.” I didn’t hear what was said to him but he replied “Oh that’s sweeeet, get hot bitch, I’ll be there in ten.”

I could only stand and stare at the fading tail lights of the car. He had used Madison, taken her virginity and now was headed somewhere to see another girl. I wasn’t mad, I wasn’t envious; I wasn’t sure how to feel about what I had just witnessed.

The next few days Madison was sullen and moody, her eyes cast sadly to the floor. Our parents kept asking her what was wrong but she remained silent. I knew why; I’d been there and knew what had put her in the bad mood. Five days later we left for our annual trip. Twelve days of fun and joy traveling down the highway in a cramped old RV with a wounded, angry big sister and my parents. The novelty of these trips was wearing thin.

The first night out I slept on the reclined passenger’s seat of the RV. Madison was poisonous and I didn’t want to get too close to her. The next morning she woke me as she pushed past to go outside, she left the door open and I could see her trying to call someone. Whoever it was didn’t answer so she left a message, “Call me. It’s okay, I’m not mad anymore about what we did in the car. You can call me.”

She was talking to the stud’s voice mail. For the rest of the day she was quiet, pensive. Her phone rang a couple of times and she snatched it up, looked at caller ID then tossed it back down.

That night after we were camped my sister and I were walking around a small lake. The sun was waning to the west dropping a trail of weak stars to light the early evening. She still wasn’t talking so I asked her what was wrong, why she was so disturbed. I already knew but I thought she might need to get it out. She shook her head, “Leave me alone” she growled, “I just have to think.”

“Think about what? What you did in the car last Friday?”

Madison grabbed my arm and spun me around to face her, eyes wide in shock, “What do you know about that?”

I didn’t want her to know I sneaked up on her, “Your idiot shit boyfriend almost ran over me. I was standing by the big tree, I was there the whole time.” She stopped breathing, her face transformed into a mask of misery, tears begin to flow. In a moment she was sobbing trying to hide her face in her hands as she blubbered. I felt bad for her so I reached around her waist and pulled her close then held her as she cried.

I’m several inches taller than my sister so she soaked the front of my shirt for a minute or two then moved back and sat down, pulling me with her. “He hasn’t called me” she admitted.

That didn’t surprise me. She was quiet but I was curious, I was hoping she wanted to talk about what she had done. Sex was still a mystery to me and I wanted to hear how she felt about it. “Is that the only time you let a guy fuck you?”

She started, looked at me warily and said “Fuck me?”

“Yeah, that’s what he did, he fucked you. That’s the real word for what happened. That was your first time wasn’t it? What were you feeling?” Madison nodded, sighed deeply then got up and walked away toward the camper. She didn’t answer my questions but she was sniffling again.

Later that night after our parents disappeared behind the folding door my sister and I got ready for bed. I grabbed a blanket and settled into the same seat I’d been in the night before and dozed off. About an hour later Madison shook me awake, “I can’t sleep. Come over, let’s talk.”

I wobbled across the small space with my cover and collapsed to the bunk; Madison crawled over me, propped up on an elbow and looked down on me. “Do you want to know what I was feeling?” she whispered. I pried an eye open to look at her. She was leaning toward me, close enough that a tit was pressed lightly against my ribs. She looked me up and down then laid her head on my shoulder, an arm over my body. I could feel her shaking as if she were cold so I put my arm around her and pulled her tighter to me. My own body began to shake.

Madison was motionless for a minute or so then she raised her head and asked “What do you feel right now?” She was trying to be quiet so mom and dad wouldn’t hear so her lips were next to my ear, her voice soft as a baby’s breath. The caress of air on my ear sent a shiver of hot sparks through me that started a fire in my balls. My heart started to thump harder causing my cock to swell. I moved away from her and tried to speak but my voice was trapped behind a large lump in my throat. I could only look at her as she smiled and asked “Are you getting turned on?” As she mouthed the words, she slipped a hand under the blanket and rested it on my growing hard-on. I was embarrassed by my reaction to her and the hand on my prick so I twisted away from her and tried to sit up but Madison held me down, grinned wider and cooed softly “This is what it feels like when someone makes you hot.” The blanket was made of thin material, not much more than a sheet but I was beginning to suffocate in the heat I was generating. I kicked it down and broke apart from my sister to cool off. She rolled to her back, unzipped her pants and pulled them down her thighs then wriggled her legs free of them. “Take off your pants” she whispered then reached for my zipper.

I could hardly move, I was so surprised at what she was doing I could only obey in silence as she urged me to lift my ass then pulled my jeans down my legs. As she pulled a pant leg off my foot I managed, “Jesus Madison, what the hell are you doing?”

She looked frustrated, “Do you want to wake up mom and dad?” I shook my head. “Then shut up and help get these off” she whispered urgently. When my jeans were on the floor she lay beside me and threw a naked thigh over mine. She was moving her leg, flexing it, rubbing mine with the length of hers. The inside of her velvet smooth leg was leaving paths of burning flesh as she moved it, I could feel her body behind the panties pressing on my hip. I felt the imprint of her hand on my stomach under my shirt, by then my cock was straining against my shorts, begging to be free. She put her lips on my ear and again spoke softly “Now you know what I was feeling.”

In a moment of clarity I looked her directly in the eyes and asked “Are you turned on now?”

Her face lit up with a wide smile, her eyes sparkled as she reached under the band of my shorts and gripped my erection. “Yessss” she hissed softly with her nose pressed against by ear. My embarrassment was rapidly dissipating, boiling away from the heat of her body against mine. In less than a few moments it no longer mattered that she was my sister, my mind and body succumbed to the feel of her hand, the press of tits on me so I rolled to my side to face her. My stiff cock was crushed between us and she rolled her pelvis toward me, pressing her groin on it. I reached down and pulled my shorts down far enough that my erection was standing rigid from its home. I caught her panties with my fingers and tugged them over her butt and down her legs. She helped take them off then threw a leg over my hips. The head of my cock was buried in her pubic hair, she put a hand on my ass and pulled me closer. My head was pounding, my heart crashing inside my chest. I felt hot but I was shivering. Madison’s body felt like it was in flames everywhere her bare skin touched mine. I moved my butt back and put my cock between her thighs, sliding along her crack. She gasped quietly and rocked with me as I began to stroke my stiff prick on her sex. She was hot and the shaft of my cock was getting wet and slippery from the fluids flowing from her, my balls were ballooning with the tension building in them. Madison rolled to her back pulling me with her in one swift motion. I went to my knees between her legs and looked down on her in the feeble light from the camp ground lamp post. She grabbed my arms and pulled me over her then worked a hand between us and grabbed my erection. My sister pulled back the foreskin, stroked me a few times then moved my engorged cock around until the head of it slipped into the opening of her body. I responded to the feel of her by pushing into her as far as I could. Madison put her hands on my ass, looked up at me and breathed soundlessly “Stay there, don’t move.”

I was vibrating with sexual anxiety, my body was tight with tension, I had to move. I tried to stay still for her but instinct overcame my will and I began to stroke in and out of the hot soft hole that enveloped my aching prick. She put her hands on my cheeks, locked her eyes on mine and followed my movement with her own. We were fucking. It didn’t register at all that I had just lost my virginity, it didn’t matter she was my older sister, it didn’t matter our parents were just a few feet away, the only thing in the world that mattered just then is what we were doing. It was all new to me. I’d been fantasizing about several girls and knew what I wanted to do with them but now that I was having sex with my sister they vanished from my thoughts in an instant. My entire concentration, my entire life force was focused on my sister. We mashed our bodies together urgently but softly, not wanting to shake the RV. Madison cautioned me to “Be careful, go slow.” We had both felt the results of mom and dad having sex in the back and she didn’t want them to wake up to the same motion. She didn’t have to worry. About the time she warned me to move slower, my balls erupted violently and I filled her with surge after surge of superheated cum. I had never before felt anything like the violent pleasure of ejaculating into Madison that night.

We lay side by side panting, cooling off. Madison used paper towels to clean up the mess then we got dressed again. When we were done she stood against me, tits mashed against my chest and kissed me softly on the corner of my mouth then purred into my ear, “You better sleep in the seat. I don’t know if I could keep my hands off you if you come back to the bed with me.”

The next morning when I awoke Mom was cooking breakfast; the bunk was a table and Madison was gone. I stretched, yawned then went to find her. Just as I got to the ground she came around the back corner of the RV, she saw me and flashed large welcoming smile, her face radiant in the morning light. She gestured to me and stepped back behind the motor-home. I went around to find her and was momentarily stunned when she palmed my cheeks then kissed me solidly on the mouth. She pulled her head back, looked at me with large blue eyes and a big smile then said “Don’t worry, I liked it.” I was relieved that she would talk to me, not avoid me or fret about what we did.

We weren’t going anywhere for a few days so Madison and I took off to the lake after breakfast. As we walked we talked. “What happened?” I asked, “How come you did that?”

“I’m not sure. I was thinking about you watching me when we had sex and began to wonder if you had been with anybody yet. I know some girls who would like to date you and they keep telling me that you’re hot and when two of them asked me if you had taken any girl to bed, I couldn’t answer them. From there I tried to imagine you with no clothes on and screwing a girl and I sort of got horny and decided to find out. Was that your first time?”

I was almost embarrassed to admit “Yeah.”

She stopped, put a hand on my arm, looked up at me cautiously and asked “What we did; is it okay”?

I leaned toward her and put the tip of my nose in her hair just over her ear as if to tell her a secret, “Can we do it again?”

She tilted her head, “Yeah, I think so, it felt good when you were inside me, you didn’t hurt like he did” then pressed her soft lips to mine. That was the first sexual kiss we ever shared and I started to swell as she rubbed her hand down the front of my jeans. We came to a small clearing on the opposite side of the lake, I sat on the grass and pulled her down to my side. In seconds I was on my back making out with my sister who was lying full length on me. The swelling had become a tent in my shorts and she adjusted her position until it was lodged in the junction of her thighs. Even though she and I were fully dressed, we dry humped with growing need and passion.

I pushed her up and said “I want to see your tits.” She grinned largely, moved to sit beside me then after looking around to make sure we were alone, pulled off her t-shirt and pushed her bra up, revealing her breasts. She took my right hand and pulled it to her left breast, I felt the firm soft mound rising from her chest under my hand; the nipple grew hard to my touch.

“Kiss it” she directed. “Kiss the end of it; lick it with your tongue.” I bent to her to obey the command. I pursed my lips over the nipple which caused Madison to take a quick gasp then she moaned delicately into the morning air as she twisted her fingers in my scalp. I moved from one breast to the other. Madison relaxed down to her back on the grass and let me explore her body with my mouth and hands. I sucked a nipple between my lips and nipped it lightly with my teeth. She arched her back, her body shuddered then she pulled my head up for another kiss. This time she experimented with the tip of her tongue on my lips. My tongue found hers and we began seducing each other with our mouths. I moved back to her tits and licked her left nipple. Madison pushed her breasts together so I could lick both at the same time. I flicked my tongue over them with more urgency, rapidly moving from one to the other. While I was busy on her tits I put a hand between her legs, she was hot, her pants were damp. I stroked the source of her heat which caused her to roll her hips against my hand, by then my cock was crying with lust, the tears from the end of it soaked my shorts. I lifted my head, looked at her and said “Let’s take our clothes off.”

My sister looked back with unfocused eyes and panted, “Not yet,” grabbed my hair again and began to toss and twist while gasping for breath. She ground her hips against the source of pleasure between her legs and growled deep in her throat. She shuddered one final time then fell back onto the grass completely relaxed. I wasn’t sure but I guessed that she had just had an orgasm. She was still for a moment then opened her eyes and looked up at me, “Damn.” She glanced down at the mountain in my pants and offered “Let’s go back to the camper, mom and dad left on the bicycles. They’ll be gone most of the day.”

When we got back to the RV we found a note from our parents. It was a list of chores and that we should have dinner ready by dark when they came back. Madison grabbed a pencil and scribbled another line at the bottom of the list. She handed me the paper then stepped behind me. The last line, in her handwriting said ‘Fuck Madison.’ I turned around to face her just as she was stepping out of her summer shorts. She nodded toward the rear of the RV and said “Let’s go back there.” I reached for my sister but she darted past me toward the back of the camper, kicking her panties off her feet as she fled. She launched herself through the air and landed on the bed, laughing at me, teasing me while she pulled her shirt over her head and tossed it in my direction. The bra was last, she dangled it briefly from her fingers then grinned as it fell to the floor. I followed the scattered trail of Madison’s clothing to the rear of the RV. I’d never seen any girl completely naked before and my heart lurched in my chest when I saw her; my semi-hard dick became her plaything in seconds.

Madison is about 5’3” and small, I guess petite is the right word. She couldn’t have weighed much over 100 pounds but she packed a lot of that in her tits. They were full, round and the nipples were stood firm from rose pink circles of skin at the end of her breasts. I was trying to pull my pants off while stumbling toward her. She giggled at me, watching me fumble with my clothes, trying to shed my shirt and pants at the same time. “You’re never gonna have sex if you can’t get your clothes off any faster than that” she said mockingly. I finally managed to kick my pants into a corner just as I reached the bed. I threw myself at her and tackled her as she tried to squirm away from my grasp. My erection was throbbing, swelling even harder as we wrestled. I knew that if I couldn’t relieve the pressure soon, it would split open like a sausage on a grill. Madison managed to maneuver out of my hold, threw her body over mine and tried to pin me down, she was laughing gleefully as she sat on me, pinning my arms to the bed. She was straddled across my chest and I was looking at her slit just inches from my face. My sister started to say something but I didn’t hear her over the thunder of blood in my ears. As I looked at her sex crack partially covered by soft dark curls something wild and instinctive streamed out of my balls directly to my mind.

I wanted to lick her pussy.

I sat up with her still on my chest; she fell off backwards to the bed. I shifted around until she was tucked under me and kissed her on the mouth. I lifted up and slithered down the bed until her pussy fell under my gaze. Madison rocked her hips, arched her ass off the bed and I flicked my tongue on the beginning of her crack. The musky scent of her sex inflamed my desire and the brief lick sent a flood of sensations through me, my cock strained even tighter against the skin holding it together. I put my lips on her pubic mound and kissed it. I heard her suck in a rush of air as her body rose off the bed again to meet my mouth. I moved my lips downward to the lips of her pussy and kissed her solidly, then flicked my tongue against her. That time she groaned out loud “Ooohhhh!” I liked the taste of her, she was slick with lust which I began to lick from her. She bucked her hips and moved up the bed as I sucked on her vaginal lips. I could have stayed between her legs for the rest of the day but my balls were screaming in agony, my cock tearing at the seams. I abandoned her sex then pulled myself up and covered her body with mine. My sister looked up at me with wide wild eyes and rasped “Why did you stop?” I didn’t answer, I only widened my legs between hers forcing her thighs apart. I rolled my butt and put the end of my erection where my mouth had just been. She moved under me until the head of my cock slipped into place then I drove it home, hard and deep. Madison gasped again and arched her back, lifting her hips completely off the bed as I started to fuck her. This time we didn’t need to be quiet or secretive. The longer we had sex the wilder we got. She was tossing and thrashing under me, twisting the blanket with her fists. A pillow got knocked to the floor and in seconds the other followed it. Madison was thrusting against me, moaning sweet agony every time our bodies slammed together. I was driving into her faster and harder, our stomachs slapping loudly when the heat finally split my erection wide open. I felt another explosion in my nuts and a river of semen and sperm poured into my sister as gushes of liquid fire.

I got off Madison but my knees were too weak to hold me up so I sat heavily on the bed next to her prone body. She rolled to her side and kissed my thigh and felt between my legs for her new plaything. My prick was coated with cum, still rigid. She stroked me with two fingers then put them in her mouth to taste my discharge, “That was a hell of a lot better than what that asshole did to me last week.”

“You told him you don’t want to get pregnant, what about now? Aren’t you afraid I’ll tag you?”

Madison rolled to her back giving me an enticing view of her nakedness and replied “Last week after what we did, I got scared and told mom what happened. She asked me if I was going to have sex with him again and I said ‘I don’t know; I might but he didn’t pull out like he said.’ Mom and I talked for a while then she asked me if I wanted birth control. I told her I wouldn’t take the pill so she made an appointment with our doctor. I got a little thingy put inside me four days ago. It’s supposed to work until the doctor takes it out.” Madison looked up at me with flames building in her eyes and said “I can fuck anybody I want, any time I want and I’ll be safe.” After a short pause to let me digest her words, she continued, “Can you do it again?” My cock twitched in anticipation of another dip into my sister. We spent almost two more hours on the bed, she let me fuck her three more times. We finally had to get up and clean the bedroom then finish the chores on the list.

By the time we returned from vacation Madison and I had screwed each other at least twice a day. Most of the time when we were on walks alone but got two more afternoons in the RV when our parents left us alone. The second time we used our parent’s bed Madison had her first orgasm while I was fucking her. At first it was a light shaking in her legs but as the climax grew in intensity her body convulsed and trembled as the sexual tidal wave washed over her while I injected doses of hot fuck juice into the tender recess of her body. She put a long scratch on my shoulder when she reached her second peak; I had to keep a shirt on the rest of the trip so mom and dad wouldn’t see it.

My sister started dating some other guy and I was no longer shy with girls; I quickly found a girl in my class who would have sex with me. Even though Madison and I were both getting laid outside the house we found time enough to be with each other a couple times a month. We used those times together to experiment, suggesting and trying new positions and sex stuff. Once we were satisfied with each other, we used our new-found pleasures on other partners.

Neither Madison nor I went with our parents again on those summer trips but my sister and I screwed steadily until she moved from home. Even now when one of us goes to visit the other, we occasionally end up in bed, laughing and giggling just like we did when we were little. Only we aren’t so little any more.

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