Well, there's not really that much to the story. Here I am, out in the street,hawking and generally messing with the patrons, when prancing up the lane comes this tall slender dark-haired girl in full pony regalia, to wit:

Knee-high black boots with hooves built into the front half of the boot, so that she was basically forced to walk on the balls of her feet, a skimpy black leather halter top and g-string, long black hair braided into a pony tail (what else?) and a long horsehair tail sticking up from her butt, to arch down to her ankles.

Her outfit was completed by a full halter/reins thang on her head, in black leather with chrome gewgaws, to include a large black bit in her mouth.

Holding the ends of the reins was a somewhat less attractive older woman dressed also in black leather, but much more concealing.

She was prancing down the lane with an exaggerated staccato pace, lifting each leg until the thigh was parallel to the ground, before placing her hoof on the ground, looking most like a trotting horse in slow motion. Her hands were tied behind her back at waist-level.

Unfortunately, it was so busy at that time, I couldn't get to the camera in time to get a pic.

But here's a pic I found on the net, if you're still unclear on the idea. :-) Google around for "ponygirl" images and you'll find plenty more.