aielen wrote:
involves a famous person you may know
The important thing is to fictionalize it enough to give yourself what is called (in Washington-speak) plausible deniability.

Really, there are any number of TV shows - "Law and Order" comes to mind as a frequent culprit - that have pretty clearly used elements of real events in a fictional setting. If what you're doing is just erotic fiction, without personal jabs at any of the thinly-disguised people involved, I would expect few if any will think you're going out of bounds.
Now, if you're worried about the legal side of it: while I am not a lawyer, if you just add a clear and prominent disclaimer that it's a work of fiction, it's not libel. That's why you see those "work of fiction ... any resemblance ... coincidental" warnings attached to quite a few things. Even things where you say to yourself, "Coincidental, my eye!"