My story started when I was 12 years old, I lived with my parents and Brother who was two years older than me. We lived in a big house close to the sea, on the day of the experience it was a summer Saturday, early evening, when mum and dad were out for the night until very late. My cousin Mary who lived across the road from us was with my Brother and me, she was 11 years old.
We spent many days together during the school holidays and went to the beach which was only 100 yards from our house and was at a quiet part of the town. This particular day it was very quiet on the beach. The three of us were wearing our swim suits when my Brother, Jim said to Mary, have you seen a penis? Which she replied, 'Yes, I've seen Rick's'.
She then said 'Show me yours'.
He replied 'Only if you show me your fanny'.
She agreed with that my Brother lowered his swimming trunks and flashed his erect penis she slipped of her swim suit off her shoulders and lowered it showing her naked form. By now I was randy and began to drop my trunks revealing my stiff cock. The three of us were sat in a clearing by the beach totally naked. My Brother and I began to wank off in front of Mary, she began to push her finger into her fanny.
We were all turned on by this action, only my brother was able cum shooting his load, but was really horny and had an orgasm along with Mary, her body went stiff playing with herself.
After about 15 minutes of this we lay in the sand total exhausted, then went skinny dipping to cool off.
We put on our swim suits and went back to our house.