'S’, my girlfriend at the time, lived at Hungerford, close to the M4. She asked me to come and see her early one Saturday evening in July. I thought she probably wanted a 'quickie' be-fore we were due out with some of her friends in the evening. When I arrived, she suggested that we went for a walk. She seemed much friskier than normal (and her normal was pretty frisky). Before we left the house, she turned round, bent down and threw her skirt up in the air, like a can-can dancer - to reveal her tight little buttocks and no panties. She wiggled her bottom, squealed with laughter and said that she wanted to take me somewhere special. We went from her apartment, along a road, then onto a footpath across some fields. We heard the background noise from the M4 and I was thinking 'where is she taking me' - I was hoping for a quiet little wood somewhere. She was getting very randy. She had got me to undo the front of her dress, to let me find she wasn't wearing a bra, in fact she was wasn't wearing anything except the dress and her shoes. She made me kiss her nipples, which were very hard, and when I finished, she did not do up the top of her dress. She was kicking her legs up and throwing up her skirt, showing me everything, and laughing. She undid my zip-per, pulled my cock out, turned round, bent over, throwing up her skirt, backing her buttocks into my cock, then jumped away, laughing. I put my cock away, and did my zipper up. The traffic noise was getting louder, and I saw a footbridge across the M4. On the other side of it I saw a small copse, and gave a sigh of relief. We were a third of the way across the bridge, when she stopped to look at the traffic. It was quite busy for a Saturday and all the traffic was travelling fast. She started waving at the cars, and I noticed that she had undone a couple more buttons on the front of her dress, so that her small breasts were completely open. There weren't many lorries, but when she saw one, she started waving. The lorry driver waved back, then just before he went under the bridge, she lifted her skirt. We heard him toot his horn, and we looked the other side of the bridge to see him swerving on the motorway, until he regained control. She loved that, doing it several more times. The next time was to a man on his own in a car, then she did to cars where there was a man with a woman. She chortled with laughter as one of them swerved on the road. 'Isn't it about time we really showed them something', she said, with her arms around my neck, kissing me - but as much for our audience as for me. A few cars tooted. She took my hand and put it on one of her breasts - that got a few more horns blowing. She pulled up her skirt, took my hand from her breast and put it between her legs. I had never felt her so wet and excited. Her hands burrowed inside my trousers, trying to ex-tract my cock, to give it as much light of day as possible. Out it came, and down she went on to it, her mouth taking in the head - but angled so that the cars could see. She said, 'Come on, pump me up', and she bent over, opened her legs, threw her skirt over her bottom. She had bent down parallel to the railings, with her bottom was just below the lower railing, so it was in perfect viewing position. 'Come on, take me', she growled. I came up behind her, and drove into her. 'Make sure they can see you' she said, and her head was turned to see the cars - the more they hooted, the more excited she became. One car swerved right across two lanes, and only just regained control on the hard shoulder. She could not last very long, and when she came she nearly collapsed, hanging on to the railing, but with me still driving into her. I was just about to explode into her when I heard the siren of a police car. She had been watching it approach, but hadn't said anything. It stopped just the other side of the bridge. I came out of her just as my spunk spurted out - some onto her, but most onto the ground. I put away my cock still jerking, took her hand, and we ran back into the fields. Fortunately there was a high bank between the motorway and the field, so by the time the two policemen climbed the bank, we were a long way away . 'Couldn't we have waited for them?' she said, laughing. She said that she was too excited to wear any panties now, so we went to see her friends as we were, although she did button up most of the buttons on her dress front.