The Nightsisters were a clan of witches that lived on the mysterious world of Dathomir. As one of the many clans of witches on Dathomir, the Nightsisters chose to live apart from these other groups choosing to develop the malicious aspects of their mystic abilities. Originally founded by outcasts who had exiled from their respective clans. In time the Nightsisters grew into a powerful force in Dathomiri politics. Like all witches on Dathomir had a matriarchical society where men lived as servants, slaves and occasionally mates. This role in relation to the Nightsisters is filled by the Zabrak Nightbrothers.