You take him slowly

The old man comes out with two shoeboxes. You dismiss the first style immediately, let him buckle your dainty feet into the shiny black leather of the next pair. You walk over to the angled floor mirror, pretending to check out the heels, actually modelling her bare legs for the crouched salesman. You make sure he gets a pantyshow in the low-angled mirror.

"I don't know," you say, biting your fingertip thoughtfully, teasingly, "they don't push my ass out much..