Depatar, also known as the City of Masks, was a floating city on the gas giant of Genarius. Unlike other Genariusan cities, Depatar was shaped like an urchin, with each spike serving as a private landing bay.
The city was created by five criminal organizations looking for a neutral ground for secret meetings. They soon discovered that many parties would use this kind of place, so they decided to open the city and make a profit of that: Depatar would allow anyone to meet and deal with anyone, both parties willing, without anyone else knowing it. Each of the five crime unions chose one representative for the five-member City Council.

See here the basic  information about the Background on Depatar