"Mercedes" by Morgan Preece (zanna@whoever.com). The narrator is a gigolo, I suppose; he hangs onto his piece of life by latching onto older women, who like him for his good looks and the sex he is able to throw their way. As he says, " Sex is all in the mind anyway and I approached each woman as an intellectual puzzle subject to physical manipulation, like one of those multicolored cubes. But things begin to change one day when he tries to seduce a rich woman who drives a Mercedes. He finds himself trapped, enslaved; and he undergoes experiences that had never even occurred to him before.

I usually don't like sex-slavery stories or those that involve piercing and diapers; but I did enjoy this story. It's hard to explain. I recommend you check it out for yourself.