Tr'a Saa was a female Jedi Knight during the time of the Old Republic. Of the Ryyk species like ancient Jedi Master Ood Bnar, Tr'a Saa served the Jedi for millenia as well due to her species long life. She rose in the ranks of the Jedi Knights to become the watchman of the sector that held the sister planets, Kiffu and Kiffex. Kiffu was home to the near-human race of beings who called themselves the Kiffar. Kiffex, they had made into their sectors prison planet, and it was here that Tr'a Saa was needed at a time of extreme darkness.
Aside from being a prison planet, Kiffex was home to a temple that held the body of the Dark Jedi Knight, Volfe Karkko in stasis. A millennium before Tr'a Saa's time, Volfe Karkko was a promising Jedi Knight, strong in the Force and renowned among the Jedi. However, Karkko was also an Anzati, a species of humanoids that supplemented themselves by drinking the 'soup,' or life essence of other beings. This fact made many Jedi Masters concerned about training an Anzati in the ways of the Force.
But since Karkko had never tasted the soup before, he was not controlled by the Anzati instinct of attaining it. However, Karkko grew curious about his species, and their infatuation with the soup. Feeling there could be no harm in trying it once, he drank the life essence from a young Jedi Knight, and it was at this moment that he fell. Eventually falling completely to the Dark Side, it eventually took the entire Jedi Council to hunt him down to the planet of Kiffex and defeat him. However, rather than kill him, they placed him in a stasis field and built a temple to honor the great Jedi Knight that Karkko once was, and to tell of his importance to his species.