It was a hot day and I had been horny most of it. I decided to take a bike ride. I set off in the hot sun and headed for the open fields near to where I live, for a bit of off road exhilaration. Twenty minutes into the ride the overwhelming urge to masturbate took hold.
I stopped on an open track, there was an old store shed to my left and a hedgerow on my right, other than that it was pretty open.
I laid my bike down at the side of the track, slid my hand under my shorts and squeezed the tip of my erect penis. I felt so horny and the thought of being caught added to it. Before long I found myself taking all my clothes off apart from my pants.
It felt great, before long I took my pants off and got ready to cum. What happened next was probably the most embarrassing moment of my life.
I could feel the orgasm building when I heard a noise on the gravel track. Looking to the corner of the hedge I noticed a bike wheel roll into view, I couldn't stop myself. Two girls in their mid-twenties stopped, sat on their bikes and watched me jerking off until I had a massive orgasm, they kept looking at each other and giggling.
After cumming I felt so embarrassed. I got dressed, picked up my bike and apologised. They giggled again and said 'Is that it then horny' and sighed. I peddled away as fast as I could.
Now when I masturbate it becomes one of my fantasies.