My bedroom was right next to the bathroom and as a young teenager beginning to wake up with erections and exploring this new found amazing thing we can do to ourselves I became obsessed with women, sex and wanking. I wasn’t popular at school so I had to make do with the internet or spying on the Mrs Breton next door when she was in her bedroom getting ready! One night my sister was having friends over as my parents were away and a sleep over so I decided to hide a camera in a bottle of shower gel. I was excited to watch my sisters friends getting a shower. Sitting there waiting for them to get a shower i learned they’d already got ready at their own places. Disappointed I was about to close my computer when I heard my sister say she was getting a shower. After dismissing the idea I thought oh what the hell I’d watch anyway. She steps into the bathroom and takes off her outer clothes. Standing in only her underwear she checks out her figure in the mirror. For a 17 year old girl she already had a great figure. Small but ample tits, curved purt bum. Her hair was long and reached down the length of her back. She was fit and she was (unlike me) popular at school. Now I see why. As she took her bra off and knickers I felt myself get aroused. Sitting there watching my sister get in the shower was turning me on. Big time! As the soap ran through her hair and over her breasts, down her legs to her feet, I was gone! Totally engrossed. Her hands slipping down between her legs and sliding back up her body. It was amazing. As she finished and stepped out I had thoughts running through my head how bad it was I got hard on my sister. Oh who cares I enjoyed it. The girls and my sister left for their night out. 2am came and I woke to the sound of giggling and laughing girls stumbling into the house. The noise continued to after 3am. It then started to go quiet. Sat up wondering if I could sneak out and catch any of them naked sleeping, the door flung open to my bedroom. It was my sister. Stumbling in she laughed ‘you’ll have to sleep on the floor little brother I need the bed. My friends are in my room’ She took off her dress and looked at me, turn around you perv! I got out of bed and laid on my sofa bed facing the wall. I heard her get into bed and while still shouting to her friends in the next room fell asleep. What am i doing on the sofa bed, this is my room! I’m always been told what to do. I got back into bed. My bed!! Laying there facing the ceiling I wondered if she was naked. I pulled the duvet up slightly. She was! Oh god, it’s happening again. My cock growing to a hardness I think was a personal best!! My sister then turned in her sleep towards me and her hand fell on my cock. Omg ! I was so excited. I reached down and holding her hand I gripped her fingers round my cock and started slowly wanking. The feeling was insatiable, it felt wrong but how can it when I am this hard. I touched her breasts. Cupping then and squeezing her nipples. I swore she smiled. She was out cold. Totally gone. Before I could justify what I was doing I was on top of her. Her legs already spread, my cock pushing through her initial tightness. As I fucked her slowly, holding my breath as not to make a noise and wake her I was sucking her nipples, one at a time, back and forth. I could feel that moment approaching when I wanted to cum. I held myself deep in her as I shot my load. Oh fuck it felt good. I pulled out and slowly got off her. I grabbed my underwear and tried to wipe away as much of my cum off her as I could. I then had a sudden moment of realisation what I’d done. In a panic I got my PJs on and went downstairs to sleep. Nothing was said the day after, but my sister was more quiet than usual. I wondered if she know. Two weeks passed and I was in my room, I could hear my sister arguing with my parents, I went into the hall to listen. I couldn’t believe what I was hearing. Fuck. She was pregnant !