A guild plugin that is similar to towny
The script could eventually work with Team by mwthorn http://one.denizenscript.com/denizen/repo/entry/87

The world is protected, the players cant destroy or place bloc, but the players can create guilds territory in that specific world. Only guild member can interact with this guild zone if the guild chief decide so.
The guild chief or guild highranked can create multiple precises zones (free/bought or location) to their guild member.

The more complicated thing now :
The guild can create alliances, and alliances can ally or make war (or be neutral)
And alliance can conquer guild territories but not destroyed them. The guild who as an alliance that is conquering their territory (by war or something like that) must pay taxes to the alliance that as conquer their territory, the guild can retake his power to be in full control (their own alliances)