Well, when I was seventeen, I went over to stay at my Aunt's home nearby for a couple of days while my home was under some renovation. My cousin was around and she was about three years older than me. I like to talk with her about all sorts of crazy stuff in her bedroom. One night, I went to her bedroom to chat with her and I saw her wearing a nice sexy little slip. I got a bit hard as I had never seen my cousin wear something like that before. Anyway, I just chatted and acted like normal. It was difficult to sleep that night as I was thinking about my cousin and her rather gorgeous body.
I got back to my aunt's home early after school the next day, and found no one around. I went to my cousin's bedroom thinking that she might be around but saw no one. Then I saw her slip lying on the bed. Suddenly, I had this urge to touch and feel the soft silky slip. I touched it and sniffed it, the smell of my cousin's perfume got me aroused. Lying on her bed, I stripped myself and started to fondle my cock and balls. Then I wrapped her slip around my cock and started to masturbate. I lost control after a while and accidently unloaded all my cum on her slip. As my cock was spurting cum all over her slip, the bedroom door suddenly opened and it was my cousin standing at the doorway! I could not stop cumming of course, but I saw her smile and walk out of the room.
I was a little shocked when I came to my senses, I got dressed and went downstairs to find her. I told her I was sorry, but she wasn't angry at all. She told me to follow her to her bedroom and she stripped herself, took her slip which was full of my cum, and started to spread my cum all over her breasts. She moaned 'J come and help me masturbate.' We ended up playing with each other.
My cousin and I still have fun together regularly at her home, but until now nobody knew of our secret relationship, which started from a silky little slip.