Life is full of erotica, if you look for it and notice it. Sexy things happen all the time. Just seeing a gorgeous young thing bend over to reveal the top of a black lacy thong is highly arousing! A glimpse of breast down a low top, a flash of panties under a short skirt are all everyday occurrences, especially in a busy shopping centre or a night out. It was one of these that gave me the horniest experience of my life. I was in Surrey for a few days and visited a friend for a few drinks. I caught a train back to the village I was staying at. It was the last one of the evening and was pretty empty. In fact, there were only 3 of us in the whole carriage. On front of me, several seats away, were a couple, in their late 30's I guessed. She was dressed in a power suit, obviously coming back from a late night at the office. He was also in a suit. I glanced at them every now and then and noticed they were deep in whispered conversation, occasionally exchanging a light kiss. Soon, however, his hand rested on her thigh and he began stroking it. She responded by putting her hand over his crotch and making rubbing movements. I had the stirrings of an erection seeing this, but watched them via the reflection in the opposite window. I could see they were watching me and then I saw the most incredible sight. She hitched up her skirt to show that she was wearing stockings and a tiny black thong. She moved it to one side and began to play with her pussy! I gave over all pretence of not looking and openly watched them. Next thing I knew, he had his cock out and she was wanking him. He just put his head back and closed his eyes, obviously enjoying it immensely, as was I! His hand strayed to her neatly trimmed pussy and she had her legs wide open. We made eye contact and she just smiled, and then stared at my crotch region where I had an obvious hard on. Taking the hint, I unzipped my trousers and released my painful erection. I slowly wanked as I watched them. He never looked at me, but she was doing the corny porno things, licking her lips and using her free hand to caress her tits through her blouse. She eventually opened her jacket and unbuttoned her blouse, so that I could see her tits encased in a white half-cup bra. She played with a nipple as I sat, entranced. Her boyfriend/husband began to buck his hips and she bent over, taking his cock in her mouth and he moaned as he orgasmed. I could see her swallowing furiously as she took it all in her mouth, then sat back and licked her lips. I was on the verge of cumming when the train began to slow and reached the next station. They stood up, straightened themselves out and got off the train, leaving me high and dry! As they walked past the window, she waved and he grinned and nodded at me. All I could do was to wave back.