Concept: The Pluton Zone is a space sandbox designed to facilitate "Space D&D"; there are space- and planet- monsters, treasures and "dungeons," as well as a feudal frontier society and some vaguely-defined & Dune-inspired "space magic" to justify the occasional Space Sorcerer and Space Cleric. People fight with space swords due to both some vaguely Klingon/Barsoom-ian space warrior society traditions as well as practicalities involving space ship hulls and systems.
The Pluton Zone is humanocentric, the presumption being that aside from occasional Vancian "Inscrutable Indigenes" or extra-weird NPCs, the sentient population of the region is entirely human-based. Society is dominated primarily by aristocratic Houses that command the majority of Pluton Zone's military and mercantile assets; these Houses are led by sundry Lords, Barons, Archdukes, Princes and the like dependent upon the status of their House, their lineage, and their holdings. Those audacious enough to declare themselves Kings or Emperors have been set upon and destroyed by the rest of the Houses for both their temerity and the implicit threat to the liberty of these Houses by such aspirations. Many Houses have complex liege and vassal relationships with other Houses.
At one time in the past the society of the Pluton Zone was occupied by a staunchly middle class democratic capitalistic homogeneous society, but things collapsed a long time ago and callous space feudalism emerged.
Tourism from the more "civilized" core zones are a major industry for safer worlds; the tourists marvel at the quaint customs and barbaric splendor of many of the societies with many taking advantage of the looser legalities and flexible regard for human rights of these worlds.