Slipping It Into My Sleeping Sister

All characters involved in all sexual activity in this story are over the age of 18. Enjoy!

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There I was, in my room late at night, jerking off as usual. I found some videos to watch while doing the act, but nothing special. I was watching this one scripted video where the dude snuck into his "step-sister's" room at night, and found her masturbating. The two of them eventually ended up going through the normal back-and-forth of oral, then proceeded to have sex. Nothing surprising.

While I was watching that video, I thought about what would ACTUALLY happen if someone did that. I didn't live with any stepsisters at the time, nor do I now, but I did live with my parents and younger sister. Isabella, my younger sister by two years, had just recently turned 19. I figured that if I were to sneak into her room, she'd be asleep like a normal person at 2 am.

Asleep. She'd be asleep. I stopped jerking off entirely, now thinking about going to her room. But I couldn't seriously go into her room, since she's my sister. The idea, however, didn't fade. I only started considering it more seriously. She'd be asleep, so no harm done, if I sneak in, right? And if she woke up, I could just say that I thought I had left something in there, and leave.

The porn video had by then ended, leaving me with nothing to distract me from the temptation of sneaking into Isabella's room. I felt my heart beating faster, as I slowly convinced myself that it would be fine. So I slipped my boxers and shorts over my boner, and stood at my door, confronting myself.

"Yes, I'll be fine, I can do this," I whispered to myself. I creaked open my door and padded down the hall to my sister's room. I lightly knocked, hoping for no response. After a moment of silence, I placed my hand on the handle, my heart racing. Never before in my life had I done something so carefully slow. I finally got the door cracked open, and gradually eased it forward enough that I could slip in. I left it ajar behind me, placing one of her various shoes at the foot of the door, to keep it from drifting back open.

"Hey." I hissed, seeing if she would respond. Once again, nothing. I then realized that I needed an actual excuse for being in her room, so I started trying to think of something that I might've left earlier in the day.

As I was contemplating, Isabella shifted, nearly scaring the shit out of me. She had turned onto her back, with her comforter draped across her midsection and the top half of her legs. I took a moment to admire her physique. Her smooth, lightly tanned legs led upwards, disappearing under the comforter. My eyes drifted higher, towards her upper chest, and face. I had never really taken time to get a good look at my sister from a non-older brother's perspective, but I did then.

I could tell her breasts were nearly C-cup-sized, giving her the look of an attractive young woman. I blushed to myself at this, hitting myself inwardly at the perviness of my thoughts. But those thoughts were still true, and so I stayed where I was, in my little sister's room, at 2 am.

Then she shifted again, moving the comforter off of her entirely, and splaying herself out on her bed. I looked across her body, feeling my dick growing in my boxers. I knew that I shouldn't have been looking at my sister like that, but that didn't stop me from doing so.

That was around the time when my brain stopped controlling my actions, and my cock started making decisions on its own. I slipped my hand under the waistband of my shorts, and into my boxers, just holding myself. I stood there for another minute, considering where I would go from there.

Then I took my hand back out of my shorts and reached over. I wanted to tap her shoulder, to see if she would react to being touched. So I reached over, and tapped her shoulder twice, waiting to see if she would respond. Luckily, she only snored lightly. I breathed a quiet sigh of relief.

I had to make up my mind. Do I go any further, or escape while I still can? If I were to get caught doing anything to her, it most likely wouldn't lead anywhere good. On the other hand, I was very horny at that point, and very excited about the possibilities of the situation. I knew I would have to get myself off one way or another.

My anxious cock made the decision for me. I slowly took hold of one side of her sleep shirt, and carefully pulled up on it. I repeated that action on the other side, going back and forth until the bottom hem of it was edging on the underside of her breasts. I was sweating by this point, I was so nervous. Pulling by each side of her shirt, I finally revealed her boobs to the chilled nighttime air.

From the instant of the reveal, I couldn't take my eyes off them. My hand shot back into my boxers, gripping my hard length. I was practically hypnotized. Without realizing it- it must have been a strong inner desire- I extended my arm, reaching for her chest like a zombie. Who knows, maybe I moaned like one too, though it would've been more of a " horny perverted zombie" moan, rather than an "I want to eat your brains" moan.

As my arm reached out, I became more aware of it, though not enough to stop myself. The temptation of her perfect exposed breasts was too much for me to handle. My middle finger came into contact first, and I froze.

Shit, was I about to wake her up? After a moment of stillness, I slowly glided my finger around her boob, feeling the goosebumps rise on the contours of it. I slowly circled it, gradually getting closer to her nipple. I had never in my life been more nervous. Or aroused, for that matter. Right before I got to her nipple, I pulled my left hand out from my shorts and held both my hands above her boobs. I knew I would have to jack off soon, or I'd bust a vein. I lowered my hands, praying she wouldn't wake up.

And then, it happened. I legitimately had my sister's boobs in my hands. While she was fast asleep. I couldn't believe I had the balls to do it, but I did. I held them for a minute longer, savoring the feeling. They were so warm and wonderfully squishy and just felt absolutely incredible in my hands. I could feel her stiffened nipples pressing into my palms. I didn't dare move much, figuring movement would probably be the last step to waking her.

I reluctantly drew my hands away, immediately wishing I had stayed where I was for just a few seconds longer. I took the sides of her shirt and taking one more good look, very carefully pulled it back down over her breasts and stomach. I backed away, and left the room, making sure to close the door behind me. I then rushed to my room, threw myself onto my bed, and jacked off, cumming harder than I ever had before. The whole time, thinking of how perfectly her cute-ass boobs fit into my hands.

After cleaning myself up, I lay there, replaying the actions of the night over and over again in my head. I ended up masturbating to the thought of my sister and her tits again, before finally falling asleep.

~

For the next few nights, I would lay in bed, only thinking about Bella. Thinking of how I touched up my own little sister, and she didn't even know it. I knew that I was already growing an unhealthy obsession, but I didn't much care. The fact that she was supposed to be off-limits for me, her older brother, probably only fostered my attraction to her. I knew that soon enough, my memories of that night wouldn't be satisfactory anymore.

Nearly a week after the first time I snuck in, Bella had a big soccer game for her university. Her team, the Panthers, managed to make the winning score within the last minute of the game, solidifying their place in the finals. After the team celebration, our family went home for the night. Our parents even let us have some of their whiskey, and we all hung out for a bit, before going to our respective rooms for the night.

I realized during our family hangout time that if I wanted to sneak into Bella's room again, that night would be the ideal time to do so. Around 1:30 am when everyone had been in bed for a bit, I was starting to feel a little antsy. Excited about what I was going to do, but nervous all the same.

After waiting for as long as I could possibly stand it, I got up out of my bed, and stood at my door, listening for any potential night-time roamers. Hearing nobody, I crept into the hall, and down to Bella's room. I gently put my ear to the door, to listen for movement. Nothing. I eased the door open, and fully closed it behind me. And there I was, back in my little sister's room. At night, while she, along with the rest of my family, were asleep. My heartbeat rising, I tiptoed to the side of her bed.

"Hey!" I whispered and thankfully got no response. I rustled her shoulder a bit, but she just turned her head to face away from me. Perfect. Like the previous time, Bella had her comforter draped across part of her. Though this time, it had strayed more upwards, revealing the clothed lower half of her body to me. Fortunately for me, she had decided on a light outfit for bed and was only wearing a skimpy pair of panties along with some unknown nightshirt. I stared at her panties, willing them away.

The idea to pull them down soon came to me, but I wasn't too sure if it was a great idea. I bent down, putting my face near her covered snatch. I reddened a bit at what I was doing but didn't stop. I closed my eyes and took a deep breath in, relishing her intoxicating scent. I nearly fell over from how distracted I was.

My eyes shot open when, suddenly, Isabella shifted in her sleep. I thought I was gonna shit my pants, it scared me so bad. Calming down a bit, I focused back in on my sister's soon-to-be uncovered pussy. I pinched the top sides of her panties, and taking a deep breath, started slowly inching them down her waist. As I was pulling down, I stared at her pussy coming into view. It looked so perfect. I figured she had recently shaved since she had just a small amount of fuzz bordering her pussy lips.

I stopped pulling for a second, to trace my finger lightly around her cute pussy. I could already imagine doing naughty things to her. When I'd finally wiggled her panties out from under her butt, I pulled them down under her knees, so they'd be properly out of the way. I took a deep breath and turned to her fully-exposed pussy. I couldn't believe I'd gone that far, and I knew I'd have to go farther before going back to my room.

I neared my face to her mound, and ever so gently, gave it a tentative lick. Making sure my sister was still sleeping, I gave her pussy another lick. My cock was straining, roughly tenting the material of my shorts. I felt a little dizzy from all the blood pulsing through my dick. The lack of blood in my brain, due to my throbbing cock, lead to me making more questionable and risky decisions.

As quickly as I felt comfortable, I took the comforter off Isabella's chest, and tugged her night camisole up, to uncover her perky boobs. After revealing them, I stared for a moment, then lowered my mouth over her left breast. I simultaneously started swirling her nipple in my mouth, and placed my hand on her pussy, barely pushing my middle finger into her warm slit.

I stayed like this for several minutes, switching between breasts every fifteen seconds or so. Keeping my finger only just in her slit, I took my mouth off her boob. Then I wiggled my shorts and boxers off my waist. I lightly took her closer hand, and placing my hand around the back of hers, curled her fingers around my hard length. I had managed to place my little sister's hand around my cock.

And so at that point, I could barely stand the wait any longer. Using her hand, I delicately rubbed myself off. When I had nearly reached the point of cumming, I took her hand off my dick, and leaning over her chest, shot my semen all over her perfect boobies.

With the aid of post-nut-clarity, I quickly took my sister's phone, went to the camera app, and took a photo of her cum covered chest. I made sure to cover her eyes, so she wouldn't wake from the flash. I texted the picture to my phone, then deleted it off her phone, and cleared the text conversation. I stood there with my shorts around my ankles and realized I would have to clean her up before my cum could dry on her tits. My cum, on my sister's hot fucking tits.

I wiped her clean, and then promptly got distracted again by her perky boobs. I could already feel myself getting hard again, and so I surveyed her body. Leaving only a second to consider what I was doing, I lightly placed my mouth on her pussy mound, gently licking her ever so slightly wet pussy lips. I poked my tongue into her slit, avoiding her clit. I didn't want to stimulate her too much and get caught with my face latched onto her vagina.

Lightly tonguing her, I reached down to my dick and furiously jacked off. Soon enough, I came again, and I moved to again aim it at her breasts. After finishing shooting my semen onto my sister's boobs, I dipped my finger in it and dripped some into her slightly cracked open mouth. Then she suddenly shifted, turning on her side to face me. I jerked my hand away, and with a slight amount of guilt, quickly wiped my cum off her chest again. I hastily pulled her clothes back into place as well as I could, then rushed out of her bedroom and back to mine. I collapsed to sleep, exhausted from my night's activities.

Fast forward about three weeks, and I was dying to taste my sister again. No porn could satisfy me, so I was pretty much constantly anxious from blue balls.

Isabella's final soccer game was also coming up, so I was planning to go back to her room that night. Finally, the evening of the game came. Sitting in the stands with my parents and other younger sister Maria, we watched as Isabella made the winning score for her team. The stands went crazy, cheering for the girls on the field.

The team's excitement carried through the trophy ceremony, and the team celebration afterward. At the celebration, I couldn't help but repeatedly glance at Isabella, thinking of my cum splatters on her chest, my hands on her sexy body, and my mouth on her sweet pussy. I was getting excited just thinking of what I might do later that night.

When we got home, we were all pretty exhausted, and all got ready for bed. I took a shower, and hung out in my room for a bit, just chilling with the lights off.

After waiting for a substantial amount of time, I got out of bed, tugging on a pair of sleep pants and a white t-shirt. I slipped into the hall, and into my sister's room, feeling more confident in myself. I checked to see if she was awake, and got no response from her. I took the sheets off her, and as carefully as I had the previous times, stripped my sister bare.

As I was letting my eyes wander over her beautiful lithe body, she shifted, laying so that she was on her stomach. Her head turned away from me towards the far side of the room, and her cute butt faced up towards the ceiling. I gently gripped her ass in my hands, feeling the perfect squish ripple through my fingers. Parting her cheeks, I got my first look at my sister's asshole. It was very cute, in an odd way. I lightly touched it but didn't dare put my finger in. I moved down to her pussy, tracing around it with my fingers.

Suddenly, an idea sprouted in my head. If I could slowly get her sleeping pussy used to a small intruder, maybe I'd be able to put a bigger intruder in it. Without waking her, of course.

So I proceeded with my plan. I first turned her over onto her back and spread her legs apart for easy access. I then inserted the tip of my middle finger into Isabella's pussy, while watching her face for a reaction. Still monitoring her face, I inched my finger farther into her warm depths. I could feel her slick insides conforming to the shape of my finger. It felt absolutely incredible, even just on my finger. When I had gotten my finger all the way in, I slowly inched it back out, repeating the process. I nearly got lost, just fingering my sister's pussy.

After a while of using one finger, I felt safe enough to start using two. I kept the rhythm slow, knowing the eventual payoff would be worth it. As I fingered her, I reached up and fondled her breasts. I rubbed her nipples on the palm of my hand, and pinched them, feeling them harden between my fingertips. The entire time, my rock-hard dick had to sit in my pants, waiting for when I would finally touch it.

I slipped my fingers out of Isabella's moist pussy, and sucked them into my mouth. I salivated on my fingers, relishing the taste of her sleeping arousal in my mouth. I could not believe I had gone this far, and I was only about to go even further. I took three of my fingers and arranged them into a triangle of sorts, then carefully pushed them into my sister's wet snatch, her puffy lips sliding over me.

I went back to watching her face, making sure I wasn't causing her any pain. I saw her face twitch a little when I had fully pushed into her. I cautiously stopped moving, and waited for a minute, before moving again. Back and forth I went, Getting her pussy used to my three fingers.

Eventually, I felt confident enough to proceed to the next step of my plan. I incrementally moved Isabella towards the center of her bed. Then, after I had removed my pants and boxers, I eased myself onto her bed. I crawled on top of her, being careful to not put weight on her.

At that point, I was positioned over my incredibly hot naked sister, hard cock pointing right at her pussy.

My heart was beating so fast. I was unbelievably nervous. I was gonna fuck my sleeping sister. I thought my cock couldn't possibly get any harder, but I think it still did. I lowered my forearms to the bed near the sides of her body for support, and looked down at my dick, peering through the darkness. I lined the tip of my cock up with her slick mound, and ever so carefully, pressed the tip against her pussy lips. I could already feel her juices on the end of my dick. Then, heart pounding, I lowered myself into her pussy.

My cock was in my own sister's pussy, while she was sleeping. I pushed my head past her lips, already feeling ready to cum. After pausing for a minute, I continued pushing my length into her.

Then she twitched. Her head moved a bit, scaring the hell out of me. I nearly pulled out then and there, scared I was waking her up. But I stayed where I was, cock partially submerged in her wet pussy, my eyes frantically searching her face for movement.

I must have waited there for ten minutes since I wanted to be absolutely sure she was still sleeping. Once I felt safe to move again, I continued inching my throbbing dick into her pussy. Finally, I bottomed out, pressing my pubic hair into her clit. I shivered in delight, feeling her inner muscles squeezing down on my cock.

I gently started moving out, then back in again. I bent my head down, and sucked one of her breasts into my mouth, fondling the other with a spare hand. I swirled my tongue around her nipple, and popping it out of my mouth, pressed my face into her soft cleavage. I closed my eyes, immensely enjoying my face in her tits, and my cock sliding back and forth, in and out of her deliciously wet pussy. I continued thrusting my length in and out of her slick hole and nuzzling my face on her boobies.

I could feel it, the time was finally coming. I was going to cum while fucking my sleeping sister's pussy. I took a few last strokes and pushed my member as far as I could into her juicy pussy. My eyes rolled back from ecstasy as I shot rope after rope of my cum into the depths of her hole. I was in heaven. I could feel the ripples of her insides massaging the semen out of my dick as I came. My hand groped her breast, and my hips shoved forwards as much as they possibly could. I could feel the mattress underneath us compressing from the force of my orgasm. Eventually, I came down from the best moments of my life and opened my eyes again.