First and foremost, I must say that this is an amazing site and I'm glad that I have found it. Keep up the good work everyone!
My experience occured whilst on holiday in Sydney about 18 months ago. The hotel where I was staying had an indoor heated pool and a separate spa that was located at the end of the pool and slightly raised. This meant that as you sat or stood in the spa, you could see the swimming pool and everyone in it.
On this particular day I decided to go for an early swim before breakfast. I was the only person in the pool area. After a few laps, I went into the spa. The effects of the hot jets of water onto my groin began to get me aroused.
Since I was the only person in the spa, I decided to be a little adventurous and slowly pulled my bathers down to my knees and positioned myself to allow the jets of hot water to aim directly onto my now-stiffening cock. The sensations were very erotic and I rotated my body around the jets to allow the water to stimulate my arse as well as my dick.
However, before I could get too emersed in this erotic experience, I noticed some people entering the pool area. A couple with a young child had also decided to go for a swim before breakfast.
'What to do, what to do?' I wondered. My initial reaction was to crouch lower in the spa and pull my bathers up. I thought, 'Bugger it!' I was too excited to stop, so I continued to allow my hard cock to be stimulated by the hot jets. The fact that there were now other people in the vicinity made it all the more exciting! I could feel my fully-erect cock pulsating, and I knew I was building up to an almighty orgasm.
My head at this stage was spinning with erotic thoughts and the combination of the spa jets on my exposed cock, my bathers down around my knees, and the possibility of being caught by the people in the pool was too much, and I exploded with a massive orgasm. After I blew a load of cum into the spa, I quickly regained my composure and pulled my bathers back up.
It was just as well because within minutes of my experience, the young mother decided to come into the spa! I was hoping that there wouldn't be any tell-tale signs of my activity!