It's late afternoon on a lovely summers day and instead of catching the bus home you decide to walk. Your route takes you alongside a large park which you choose to walk through rather than around and after a hectic day in the office, you enjoy the peace and tranquillity.
Although you have never used it, you are aware of the small toilet block near one of the entrances, hidden behind trees and other foliage. As you walk you become increasingly aware of the effect two cups of coffee and a glass of water are having so you head towards it.
As you enter the inside looks very gloomy after the bright sunlight and you step up to the stall, undo your zip, release your penis and wait for the relief to begin. It doesn't take long and once in full flow you look around. It is only then that you see at the far end of the row another man standing close in to the wall with only his upper body visible above the porcelain modesty screen.
You think nothing of this and given the great British reserve in these circumstances, you just look down and concentrate on not splashing your shoes.
Out of the corner of your eye, however, at the extreme edge of your peripheral vision you become aware of small, almost imperceptible, regular movement from the other man. A surreptitious glance towards his direction confirms the movement is coming from his upper arm and is obviously connected to an activity lower down. He is studiously looking at the wall above his head and does not return your look.
You realise he is masturbating albeit gently, and suddenly you are intrigued. Up to now you have never given much thought to other men doing what you do quite frequently in the privacy of your home, but there is something about the fact that somebody very close to you is doing it, and it excites you.