I had lived with my flatmate Karen for about four years, and we had sex often. It was almost a ritual. After her boyfriend or lover had left, I would climb into her bed and fuck her one last time. Sex with Karen as excellent she was physical, open to experimenting, and loved public sex and showing off. What I loved most was that she would have an orgasm, and you couldn't help to hear it even outside. She knew this, and it would excite her to know someone might listen to her fucking.
It was always a challenge to find an opportunity for us to have sex when she had a boyfriend staying overnight. However, one occasion, I heard her go to the bathroom after sex, so I waited and followed her to the bathroom, where I fucked her sitting on the vanity. That was one of the only times she came quietly.
Life became fascinating when Karen received a call from her younger brother that he had his mate transferred to work in the city. He asked if Karen would show him around and help him find a place to live. At the time, Karen was 25, and he was just 18 and would arrive by bus the following Saturday.
Young Mark arrived on Saturday morning. Karen picked him up and returned him to the apartment to drop off his bags. She said she would show him the sites and swim at the beach as it would be hot. She asked if I would like to join them because the barracks were near the beach, and she wanted close and easy parking. The other advantage was that a section of the beach was a designated nudist beach.