Petrusians were a race of sentient beings, a species hailing from the world of Petrusia. Kristiss, along with Rythus, her father, were both Petrusians. Some Petrusians were forced into slavery by the Galactic Empire at the Imperial outpost of Kullgroon; this drove Kristiss to enlist the services of Lando Calrissian, a smuggler, to deliver weaponry to Kullgroon so the enslaved Petrusians could liberate themselves.