So I edged round our car and found myself beside the woman from the next car who I later got to know and who was called Mary. I could feel a bit of dampness coming on and then I noticed the other woman's hand was inside her nickers.The man and woman were certainly at it. She was naked above the waist and as near as makes no difference below.His left hand was round her back cupping about 36 inches of B cup while between his first and second fingers he was rubbing her nipple. I could just seen his right hand work working on her crotch.Mary looked round; her eyes had that rather out of focus look that comes over people as they become worked up. Her breathing was becoming audible. In fact she was making two noises at the same time - an in-out one a second breathing and just before each inhalation a moan-grunt of pleasure. "Help me" she said. "Unhook my bra." She presumably didn't want to take one hand off her pussy.Neither did I, but their are special things girls can do like taking a bra off without taking a blouse off and unhooking a bra one-handed from behind.Her boobs fell forward and as a flat-Pat I looked enviously at their fulness.Half an hour before I would never have thought I should have been frigging myself in public, watching another girl approaching orgasm while another couple were hard at work in a car.I did not notice my boy and didn't need him at that moment. I suddenly wanted Mary. I wanted to be underneath her with a strap on.