Societies are not dynamic like that, they always exist from game start, yes they can be hidden but they have to be predefined in the code before you launch the game. You cannot generate a new society out of thing air in the middle of the game in the same way you can create a title etc.
Also even if we could we would not, this is already perfectly handled by plots and factions. There is no reason to make an entire society for this.
Also even if we could we would not, this is already perfectly handled by plots and factions. There is no reason to make an entire society for this.