Master Zen has run multiple events like this in Phillly to widespread acclaim. I know many NYC providers frequent the DC area, so if interetsed, check out the link below and let him know of your possible interest:
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http://www.theeroticreview.com/discussion-boards/meet-and-greet-42/baltimore-dc-mng-22983

I never look at the M&G board and wouldn't have know about this otherwise.

That's a private, upscale venue.  

Maple Lawn / Fulton