So I will start by describing myself. I’m 18 years old, not that good looking. I have dark blonde hair, green eyes and a bit of a tummy. Not huge, but it’s there. I’m still fit as I play a lot of sports and to be honest, I masturbate a lot. I have a huge sex drive and it doesn’t seem to matter if I wank everyday or not, I still always seem to want more.
So it all begins with me getting sick. I had been in hospital for about a week. I had gotten a very bad chest infection and after a week of it they sent me to hospital to get stronger treatment. I had been in and finally gone home. I had now been home for another 2 weeks and I was finally feeling like my old self. Needless to say, I hadn’t blown a good load for 4 weeks and I felt like my balls were going to explode inside my sack. They felt so swollen from not having released any sperm for so long.
It was currently 1:00am and I thought after lying on my bed for hours unable to sleep I would go to the bathroom and get a load out, thinking this would help me rest. I got up and headed to the bathroom. When I got there, the door was closed and I could hear the shower just starting. You could always tell when it had just started, the pipes make a soft squeal noise. Who the hell was in the shower at this time. I looked around and spotted my sisters door slightly open. I headed over to peek inside. When I looked in I could see Selena on her bed. It must have been Matt, her boyfriend in the shower. He stays over sometimes after they’ve been out late.
So at this point I should describe Selena. She is very slim, athletic, long beautiful blonde hair, bright blue eyes, a nice set of C34 tits and a very tight flat stomach leading down to her magical crotch area. The front has the perfect v shape and the nice small gap in between her legs. Her butt is just as tight and firm, with a wonderful lift, giving her the perfect bubble look. She was 17 years old.
So while my parents always thought Matt stayed in the spare room, I knew he often stayed in her room until early morning then he would switch. I also couldn’t help but to notice how stunning Selena looked, lying there on her bed with her tiny lacy top and shorts on. She often slept in these. I also knew she would not have panties on under the shorts. Her chest looked wonderful, raising and lowering with her breathing and her tight tummy showing itself to me. My cock got very hard very fast. I could swear I had the biggest boner I had ever had, looking at my younger sister.
I could no longer hold back, as I slowly entered her room. I crept over to her bed and was enjoying looking her up and down. She had her sleeping mask on, which meant she was tired and didn’t want to be disturbed. My mind was going crazy with thoughts of what I could do. Knowing everything in my mind was wrong I tried to tell myself to leave. But with Matt only just having gotten in the shower he will be gone for a few minutes at least. I decided to lie down on her bed next to her, and just gently cuddle her. I slowly went around the bed and sat on the side, I rolled me legs up and lay back onto the pillow. I rolled over and wrapped my arm gently over her waist and rested my hand on the soft, smooth and wonderfully flat tummy. It didn’t take long before this wasn’t enough.
Without even thinking about it I decided I was going to fuck her until I was ready to release my built up pressure and by then I could just sneak out and wait for Matt to leave the bathroom and I could go and blow my load. Remembering that she would not see me with her sleeping mask I slowly moved up until I was kneeling at the end of her bed. I rolled her hips back flat on the bed and very carefully started to slide her ankles apart. Selena stirred, “I’m tired Matt, but if you want to then keep it quick. I will just keep resting if you don’t mind. Oh yeah, remember to use the condoms ok. The doctor took me off the pill ok”. I was stunned and in heaven. She was not even going to look and see who it was and she didn’t care if she got fucked while she slept. “ok” was all I responded with. I didn’t want her to recognise my voice.
Of cause I had no condoms to use and I didn’t know where hers were so I just stuck to my plan. Pull out and sneak back to the bathroom to finish when I’m ready. I slid my boxers down to my knees, freeing my 8 inch cock. I was surprised by how much pre cum was flowing from it’s head. It was leaking down my shaft and over my balls. I got off the bed so she would think I got the condoms and put one on. I then got back on the bed and slid up between her legs, this time moving them open with ease and no worry about if she would look. I didn’t know what ways Matt would have fucked her, knowing that I’m sure he had, so I had to guess and hope she would not notice or care. I picked her long smooth legs up and placed them over my shoulders, lifted her hips up and placed her pussy in line with my cock, so she was resting on my thighs.
I hesitated for a few seconds, again trying to tell myself to stop, she was my sister. I also checked to hear if the shower was still running, and it was. I gently pulled Selena’s little silky lace short to the side, allowing me to slide my cock up the leg and gently start rubbing my slimy head over her slit. My pre cum was flowing from me, almost as much as if I was cumming. I was gushing all over her slit, as I slowly dipped the tip into her, also allowing more pre cum to flow into her. “Matt, make sure you have the condom on, I’m right in mid cycle and have no morning after pills either. The doc said they were making me feel sick. Just go in the dom and throw it down the loo” said Selena. “Ok, no problems” was all I answered as I began to push in.
Selena was tight, but with all my fluids flowing into her she was nice and ready. Slowly I went deeper and deeper. I did not find a hymen, which was to be expected and actually made it easier to fuck her and not have her know it was her brother. Her vagina muscles were tight around my shaft and she seemed to be able to allow my thick cock to just slide nicely into her. I was about 5 inches in when I felt my head hit something. Selena gave out a soft moan and tightened her pussy around me. I must have reached the bottom of her vagina. I was now slowly sliding in and out working myself slightly deeper with each inward stroke. Holding her hips firm I pushed harder into her. Another ½ inch slid in. My head felt like it was being choked inside her. With another hard push, I got to 7 inches in, leaving only an inch to go. But something felt different now. I wasn’t sure what but my cock seemed to slide in more freely and it was not being choked anymore.
So with that out of my mind I began to pump into her with smooth rhythm, my cock now sinking to the hilt inside her pussy. I knew I would not be able to hold on long so I sped up. Pushing deep into her insides, and I could even see the small bulge in her tummy as I pushed in. I knew I was in her womb, I must have broken through her cervix, which did explain why she got so tight, then once I was in it got easier again. I knew my pre cum was already flooding into her, and I knew I needed to pull out and stop, but something about the idea of filling her very fertile womb with my sperm and getting her tiny belly pregnant with my baby just seemed right. Without thought I just pushed even harder into her pussy, driving myself ever closer to the point of no return.
Right then I felt Selena’s pussy tighten around my shaft. she mumbled and then went silent. Her tight pussy relaxed around my cock and again I was able to push as hard and deep into her as I liked. I knew she must have orgasmed and then passed out. I also knew that it meant she wouldn’t feel it if I blew inside her. That was my last will of restraint gone. Holding her hips tight, and a final thrust, I pushed deep into her fertile womb and released. My shaft fattened up and I felt my sperm rushing down it’s centre. My cock head swelled and bucked inside her uterus and the first load fired into her. This released me. As I felt more and more sperm flow down my shaft. Spurt after spurt of my baby making seed jetting into her insides, coating her womb in my love. I was unable to stop as my cum just kept pumping from my balls and down my throbbing cock. Another, and another, and another load of sperm spilled into her belly. I could even see the loads bulging against the inside of her tummy as they left my cock in search of her sacred treasures. Still not able to control myself, more cum continued to spill into her uterus, filling her womb beyond full. I could now see her tummy was starting to swell just a little. But even so my cock was wedged hard into her cervix and none of my seed was getting out, even though I continued to pump more into her.
Finally after a couple of minutes I stopped flowing, and I gave few little pumps into her to make sure every last sperm was inside her womb. And then gently began to withdraw. Slowly I pull back, realising that even as my cock left her womb, she still had a swollen bulge at the base of her belly. I was also surprised to realise that only a small amount was coming back out. I slid from her pussy and watched. With her hips still up on my thighs so her belly was down, gravity was keeping my baby making seed inside her.
I slowly got out from under her, placing her spare pillow under her hips, keeping them slightly elevated so my load would stay inside. I got my boxers and pulled them back on. I check one last time to see if my load was leaking out, and was pleased to see very little was. I left her, knowing by the time she got up in the morning my load will have soaked into her body and she will have my baby growing inside her womb.
I slipped back to my room and went to sleep. I wondered if Matt would even see that under the sheets her hips were raised. I hoped not.
The morning came and I was having breakfast when Selena came down. She has a big smile on her face and she seemed to be glowing. “how was last night” I asked. she replied. “I heard Matt having a shower about 1am, so you must have been late home” I questioned. “Yeah he had a shower then came in and cuddled me for a while then went to the spare room”. I knew she was lying, cause she thought she had fucked him last night.
After breakfast I went back upstairs and found Matt brushing his teeth. “so, you were late home” I again asked. “Yeah I had a shower and went straight to the spare room for sleep”. I knew this meant he hadn’t seen Selena’s hips up, since he didn’t go to her room.
A few weeks passed and it had only started with Selena saying for the first few days that her tummy felt bloated and her skirts felt tight. It lead to her being sick in the mornings and eventually going to the doctors. I was intrigued to find out how I did when she got back. “How did you go, did the doc say anything about why your sick”. “yeah, but I’m not sure how it happened” she answered. “What happened”. “I’m pregnant, I only had sex twice with Matt, and he wore a condom both times. Whats worse is the doc has said that I have triplets growing in me”.
I was so excited to learn that I had not only knocked her up, but I left so much sperm in her womb, and that she was so fertile that I had given her 3 new lives to grow. And of cause the best part, she still had no idea it was me. She thought I was Matt, who she had broken up with 2 weeks ago when he moved to the other side of the country, leaving no contact details because of their messy break up. I had gotten away with it and she would not be able to confirm any details about that night with Matt. I was going to be a daddy to 3 babies and my sister to be their mother. Although she would never know I was their father.

story by: Sisterly Love

Tags: rape incest fantasm non-consensual sex sex story

Author: Sisterly Love

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