Flass was a farmer on the planet Ceriun about 1000 BBY and the son of Morro, the headman of Drop Canyon village. He was an associate of Tenno, taking part in his plan to take possession of a holocron that a dying Jedi Knight had passed on to the village elders and turn it over to the Sith in exchange for passage offworld.
When Tenno lost his nerve after killing his father, Ka'arn, Flass took charge and ordered Morro to stand aside and hand over the holocron. When Morro defied him angrily, Flass killed his father with his axe, precipitating a brawl between Tenno's gang and the elders. The fight was interrupted by a Sith Lord who took the holocron for himself and contemptuously slew Flass with his lightsaber.