When I was a senior in high school, I was obsessed with sex like most boys my age. I jerked off several times a day, usually concentrating on Mary Ellen’s big tits, or at least my image of what they looked like. I knew I would never get my hands on them, but I spewed gallons of cum pretending she was standing in front of me naked and letting me play with them.

I never thought much about my sixteen-year-old sister Ann. She was a pretty girl with blond hair and blue eyes, but tiny, barely five feet tall, and almost no tits. She did have a nice ass that looked good in a pair of shorts, but back in those days I was more of a tits man, or so I thought. That all changed the night I walked into the bathroom as she was getting out of the shower. 

Ann was as shocked as I was, both of us frozen in place for several seconds. She stood in front of me completely naked. I had never seen a naked girl except in magazines. I stared at her pussy which puffed out from between her legs like a peach covered with blond curls and a dark gash down the middle. Her perky hard nipples poked out from the small swells on her chest. 

My cock immediately grew hard. After a few awkward moments, I mumbled an apology and left. I went to my room and spewed a huge load into one of my tee shirts. I lost interest in Mary Ellen’s tits and masturbated to images of my naked sister. I began hiding in her closet to see her naked again, and quickly discovered her firm ass cheeks separated by a dark cleft were just as appetizing as the rest of her, particularly when she bent over and exposed her pussy.

Ann might have remained a masturbation fantasy if it hadn’t been for the family vacation that summer to Cape Cod. On the way there, we stayed in a motel in a single room with two double beds. My dad was too cheap to spring for another room. Ann and I had to share a bed while my parents slept in the other one. 

Ann came out of the bathroom wearing a nightshirt without a bra, oblivious to the effect it was having on me. It was difficult to keep the hard-on making a tent in my pj’s from showing so I quickly slipped under the covers. Ann bent over to pick up her towel. Her nightshirt rode up and exposed a pair of blue cotton panties wedged into the crack of her ass. Pre-cum was already leaking from my throbbing cock. 

I needed relief in the worst way. Once the lights were out, I rolled onto my back and gently began stroking, trying not to disturb Ann. I didn’t expect what happened next. She shifted on the bed, and her ass cheek pressed against my thigh. Pushing caution to the wind, I rolled onto my side and draped my arm over her body pretending to be sleeping. My hard cock wedged between her ass cheeks through her panties.

When Ann didn’t move or respond, I assumed she was asleep and hoped she stayed that way. I slid my hand under her nightshirt and slowly inched it up her stomach. My cock jumped when I touched her hard nipple. I rubbed it with my fingertip and slowly moved my cock up and down between her cheeks. 

When I rolled her nipple between my thumb and forefinger, I heard Ann moan. Was it involuntary or was she aware of what I was doing? It didn’t matter to me. I was too far gone to stop. My hand slid down her stomach and under the waistband of her panties. My fingers moved across her swollen mound, and then her slit. It was slick with moisture.

Any doubt about whether or not she was sleeping was erased by what happened next. Ann moved her hand over mine and directed my fingertip to a little nub near the top of her slit. I didn’t know what a clit was back then, but it was clear she wanted me to rub it by the way she was moving my finger. 

Her breathing became more rapid and erratic. Soft moans escaped from her throat. My finger continued to rub the tiny nub in circles, applying more pressure and going faster. She grabbed my forearm, digging her fingers into the skin. Her body began to shake. She bit her lip and stifled a scream. I kept rubbing and she kept shaking. She took the finger that had been rubbing her nub and guided it down her slit. I felt it slide into her moist entrance.

I had never fingered a girl, but I was familiar with the basics from locker room talk. I pushed and felt it go deeper. She was tight but seemed to stretch open as I inched my way into her body. I buried it all the way to the knuckle. The heat of her pussy throbbed against me. I pulled it out and pushed it back in. I did this again and again. I could feel her moving with me.

I was fingering my sister. I couldn’t believe it. My poor cock was throbbing and still pressed tightly between her ass cheeks, sliding up and down in a slow fucking motion. Ann’s breathing got faster. I could feel her body tremble. She pressed her face into the pillow to muffle a scream. Her pussy clenched and spasmed against my finger. Sticky secretions dribbled down my hand and soaked into her panties.

My head became dizzy. I knew the feeling. It happened when I masturbated. Cum boiled in my balls. My cock swelled. Hot cum exploded from the tip. Spurt after spurt shot up her back. My finger was still buried deep inside her pussy. I felt her shudder one last time, and then she went limp. Cum continued to ooze from my cock and soak into the back of her panties. When it was over, I pulled my finger out and sucked it into my mouth, savoring the taste of her juices.

The next morning we packed the car for the six-hour drive to Cape Cod. I didn’t have a chance to talk to Ann about what had happened and, to be honest, I wasn’t going to. She didn’t bring up the subject either. That didn’t stop me from obsessing about it in my mind. The tight shorts she was wearing and tee shirt with no bra didn’t help. 

We climbed into the back seat. This was in the days before seat belts. Ann said she was tired so mom gave her a blanket. She threw it over our laps. Ann pulled it up to her neck, rested her head on my shoulder, and closed her eyes. Our thighs were touching. My cock grew hard. I was going crazy. I had to do something. 

After last night, I was feeling bold. I dropped a hand onto Ann’s thigh. She shifted in her seat, turning slightly away and spreading her legs. It seemed like an invitation to continue.  My fingers moved up her inner thigh until they brushed against her pussy through her shorts. She spread her legs wider. I cupped my hand over her mound, wondering if I had gone too far. Ann answered my question by moaning and squirming against me.

There was no way Mom and Dad could see what we were doing under the blanket, not even in the rearview mirror. My fingers dug into her swollen mound through her shorts and panties. Ann turned her face towards my shoulder and gasped. I pulled the crotch aside and felt the moist heat of her bare pussy. My fingertip found the tiny nub at the top of her slit and rubbed. 

Ann squirmed in the seat. Her breathing became erratic. I looked in the front seat. Mom and Dad had their eyes focused on the road and were discussing a song on the radio. I slipped my finger through her folds and pushed it into her pussy. She slumped down on the seat, humping against me as my finger moved in and out. Her pussy exploded, drenching my fingers and hand with sticky secretions. Ann’s squeal was loud…too loud.

I quickly pulled my hand away. Ann sat up as Mom turned to look at us. She had her head on my shoulder and appeared to be resting, although her breathing was still heavy.

“Is everything alright back there?” Mom asked.

“Uh, yeah,” Ann answered. “I fell asleep and woke suddenly when the car hit a bump.”

“Yeah,” I said, playing along. “It woke me up too.”

“Okay,” Mom smiled. “You kids go back to sleep. We’re going to stop in an hour for a bathroom break.”

My cock was about to explode. A huge wet spot had formed on the front of my bermudas from all the precum leaking out. Once Mom had turned her attention back to dad and the road, I threw caution to the wind and unzipped them, pulling out my hard cock. I didn’t think mom or dad would notice me jerking off under the blanket, but of course, Ann did.

“Can I see it?” Ann whispered in my ear.

I held the blanket out far enough so she could see down into my lap. Ann moved her head onto my chest to get a better look. Her fingers traced the contours of my cock. She moved them to my crown and felt the sticky precum leaking out from the tip.

“It’s really beautiful. Is this the stuff that makes babies?”

Ann kept her voice low so Mom and Dad couldn’t hear. Fortunately, the radio in front was loud enough to drown out any sounds.

I shook my head. “No. There’s a lot more when that happens.”

“You mean like last night. The stuff you shot all over my back?”

I nodded.

“Is it going to happen again?”

“It will if you make it. Do you know what a handjob is?”

“Sort of. I know Jenny gave one to her boyfriend. She said white sticky stuff comes shooting out. Is that true?”

“Yes. It’s what makes babies. Would you like to see?”

She nodded. I showed her how to wrap her fingers around my cock and stroke. Her tiny hand barely fit around me.

“Squeeze a little harder and go a little faster,” I instructed.

Ann kept her eyes glued to my cock as she stroked.  I began thrusting up into her hand each time she stroked. It wasn’t going to take long. I could feel cum churning in my balls. My breathing got heavier. Ann stroked faster. I lifted my ass off the seat and stifled a grunt. A jet of hot cum erupted from the tip and bounced off Ann’s cheek. More shot up her arm and splattered her top. Some landed on her thighs. The last few drops oozed over her hand.

“How are you kids doing back there?” Mom asked.

We quickly pulled up the blanket and pretended to be asleep. Mom turned around to look at us, then turned back towards Dad.

“They’re sleeping like babies, honey. Do you mind if I put my head in your lap and get some shuteye?”

Dad chuckled. “The last time you did that, you didn’t get much sleep as I recall.”

“Are you complaining?”

Mom’s head fell below the back of the front seat. Ann pulled her cum drenched hand from under the blanket and examined it. 

“Wow. This stuff really makes babies, huh?”

I shrugged my shoulders. She stuck out her tongue and tasted it, then licked some from her hand.

“It tastes a little weird,” Ann giggled. “That’s gross isn’t it?”

No more gross than my licking her pussy juice from my finger, but I didn’t tell her that. It was then that I realized Mom wasn’t exactly sleeping. We could hear soft sucking and slurping noises coming from the front seat. Dad was biting his lip and trying hard to concentrate on the road. It took me a second to figure out what was happening. I knew girls did things like that from locker room talk, but Mom? Did she really have Dad’s penis in her mouth?

Ann heard the same noises but was clueless. She looked at me. “What’s Mom doing? Is she chewing gum in Dad’s lap?”

I shrugged my shoulders. I didn’t want to explain it to her in the car. The noises got louder. Dad’s eyes grew big. Suddenly the car swerved. His face scrunched up. I knew that look. He was cumming. Was he doing it in her mouth? Mom answered that question when she sat up, wiped her lips, and swallowed. I was shocked. 

It would be another hour before the next rest stop. Ann fell asleep on my shoulder. I closed my eyes but couldn’t sleep. The image of Mom’s lips wrapped around Dad’s cock was stuck in my head.