Definitely one of the more memorable places in FF7.
I don't think it's just a brothel though, cause that'd imply it's plainly about sex - it's more of a fetish club where people can pay to be decadent and slightly naughty in a controlled establishment, away from prying (and judging) eyes.
With the option of getting laid. ;]
I never really understood what President Shinra was up to in one of the rooms though...