"Have you ever had your body painted?" he asks.
"No," I reply.
"Here's my card," says Simon-Naked-David. "Call me any time."
By the end of the night, my pocket is full to bursting with the business cards of various body-painters, existentialist mimes and performance artists. Everyone here's got an angle. The bizarre hotchpotch of bygone pop stars, Hollywood actors, pseudy European artists and dour models is charmingly anachronistic, like something out of an Andy Warhol party. I stand, fascinated, in the corner, and wait for something weird to happen. Simon-Naked-David turns out to be all talk, however. He stays clothed.
David Bowie, I guess, has always attracted a curious mlange of outlandish hangers-on and professionally "interesting" people. This is understandable. Bowie, the man who wrote such paradoxical and enigmatic lyrics as "The Jean Genie loves chimney stacks", and "That weren't no DJ that was hazy cosmic jive" could expect nothing less.
But the sad truth of the matter is this: in the past, everybody who worked in a clothes shop wanted to look like David Bowie - and now David Bowie looks like someone who works in a clothes shop.
He is, I've been told many times, a thoroughly likeable chap. He arrives a fashionable 36 minutes late, and grins with polite charm. He stays for an hour, and behaves with such temperate normality that one could almost forget he's enormously famous, if it weren't for the fact that he's flanked constantly - albeit discreetly - by four huge and terrifying bouncers.
The two phrases most used tonight are: "He's not very tall, is he?" and "doesn't Shirley Bassey look GREAT?" Shirley Bassey arrives early, sending a ripple of excitement through the throng. The paparazzi snap furiously, lighting up Cork Street like an electrical storm.
"Wow! Wonder if she'll sing?"
"Doesn't she look young?"
One man chats to her for 10 minutes, and comes away with his brow furrowed. "What happened?" I ask.
"She totally denied coming from Cardiff," he replies, mystified, "and said that she doesn't sing. She's a real weirdo."
And then the terrible, embarrassing truth dawns on us all. It isn't Shirley Bassey. It's Moira Stewart.
And what of the paintings? Like David Bowie's work in general, some are inspired, some are awful, all are showy. They're an eclectic mix of African and European, with a smattering of pop star-ish portraits, installations and sculptures. Sketches of Iggy Pop hang next to oil reproductions of adverts for African hairdressers, which sit next to miniature silver sculptures of his wife, Iman's, head, which are surrounded by his now famous Laura Ashley-esque wallpaper.
The work could be that of a dozen different artists. That has always been the way with Bowie the chameleon, but he claims that his art is more meaningful to him than his music, more From The Heart. I cannot comment on this, as I have no idea what particular state Bowie's heart is in - but one gets the impression that his African work, say, is inspired by a few hasty visits in a limo.
The art establishment has embraced him, to the extent that the Saatchi collection has already bought two. The work is selling surprisingly inexpensively: from £350 to the low thousands, which is how much an unknown artist would sell for. It was Brian Eno who convinced him to exhibit - he wouldn't have done it otherwise - and one gets the feeling that Bowie isn't that bothered about how his work is received.
By 8pm, the celebs - Jeremy Irons, Gina Bellman, the drummer from Queen and Martin Kemp - have left, and the paparazzi are beginning to drift away. Of the Bowie fans who earlier littered the street, only two remain. Their names are Weird and Gilly and they follow him everywhere. Bowie has left, but they are, they tell me, staying behind. To "drink in his essence".