I was 13 at the time and had discovered masturbation some six months previous. I was still experiencing the occasional 'wet' dream at night, based on events which may have happened during the day. I distinctly remember one time I was staying at my aunt's house for a few days during the summer, with my cousin who was the same age as me and his older sister Lauren who was three years older. Me and my cousin were fooling around in the back yard when he gashed his knee and his mother, my aunt, had to take him to the local hospital to get his wound stitched. I stayed at home as I did not want to be sitting around at the hospital for hours and hours, and played some computer games on his PC.
About 30 minutes after they left I heard his older sister Lauren come home and go straight to her room. She had music playing in her room, and it was pretty loud. I went along to her room to ask if she could turn the volume down, and found her door ajar. I peeked through the gap and saw Lauren laying back on her bed relaxing. The angle at which I looked through the gap between door and frame meant I could see from her shoulders to her feet, but her head was obscured. I was about to knock and enter her room when her hand crept down and began to lift her short skirt up. I stood there transfixed not knowing what was about to happen. She began to rub her pussy through her bright red panties whilst her other hand massaged her breasts. My cock began to stiffen as I carried on watching my sixteen year old cousin playing with herself.
She pulled her shirt up and freed her breasts from her bra. My first pair of live breasts were before me and she started to pinch and rub her nipples. I could hear her heavy breathing over the music as her other hand continued to press and rub deeply into her pussy cleft through the panties. They began to darken with moisture at which point she wriggled them down to her knees and plunged a finger deep into her pussy hole. I could hear her murmuring to herself whilst she pistoned her finger in and out of her pussy. My cock was now at full attention and my tight underwear pressed it flat against my stomach.
Lauren rolled onto her front and began humping her hand whilst still fingering her pussy. I had the best view ever of her pink pussy and ass as she rose up and down on the bed. 'Oh yes' I could hear her mutter, as her orgasm neared. By now my cock was leaking into my underwear and I could feel that tingling sensation deep in my groin. I held onto the door frame and stared at my cousin as she ground herself onto her hand beneath her. I could feel my balls begin to contract as the sensation in my groin increased. By now Lauren was frantically pumping her pussy with her finger as my cock spasmed in my pants. My legs felt weak as I filled my underwear with spurt after spurt of jism, just as Lauren cried out in orgasm. I almost fell to my knees watching her as she gripped her pussy and pumped her thighs.
I'd had a 'wet' dream but was not asleep! I crept into the bathroom and cleaned myself up. Lauren was still face down on her bed as I returned to my cousins room. I put on his headphones and began listening to music just as Lauren walked past to go to the bathroom. 'I didn't know you was at home' she said with a bemused look on her face. I repeated what she had said back to her, as she left the room. Later that day I 'found' Lauren's still damp red panties in the hamper, and began my masturbation history to the sights and smells I had experienced that day.