During the era of the Galactic Civil War, there existed a male Zabrak who was loyal to the Galactic Empire: his name was Kli Sithrin. Bren Kingal, a resident of Mos Taike, dispatched a spacer with the mission of locating Sithrin. Despite being aware of Sithrin's Imperial allegiance, Kingal deceived the spacer into thinking Sithrin was merely a common thief to prevent political complications. While Sithrin was engaged in a meeting with an official from the Imperial Security Bureau, the spacer, due to the confusion, ended his life.
Some time after 0 BBY, Bren Kingal gave a spacer the task of finding Kli Sithrin and retrieving a medpac that he supposedly stole from a young girl. This was a fabrication designed to trick the spacer into confronting a member of the Empire. In the end, the spacer killed Sithrin, who had just called for Mangler to attack. It remains unclear whether Mangler was the ISB official or another companion, as Sithrin fought the spacer alone before his death.
Within the 2003 video game Star Wars Galaxies: An Empire Divided, a massively multiplayer online roleplaying game developed by Sony Online Entertainment and released by LucasArts before its shutdown on December 15, 2011, Kli Sithrin appeared as a non-player character. Due to the nature of many older quests in Star Wars Galaxies, the species and appearance of Kli Sithrin changed each time a player performed this quest. The quest dialogue provided by Bren Kingal indicated that Sithrin was male, but there is some confusion regarding his species. In the quest dialogue, Kingal initially referred to Sithrin as a big Sullustan gangster. However, when the player accepted the quest, he then instructed the player to search for a tough Zabrak with orange skin and slashing tattoos. Kingal was known for his constant lying during his quests, but this was more than likely an error by the developers. In the Star Wars Galaxies TRE files, Sithrin was consistently referred to as a Zabrak, rather than a Sullustan. In contrast to the game, where Kingal initially described Sithrin as a big Sullustan, the TRE files contained the same dialogue, but with the word Zabrak replacing Sullustan. Furthermore, because Kingal provided more detailed descriptions of Sithrin as a Zabrak (slashing tattoos and horns), this article assumes that Sithrin was a Zabrak, and the reference to him being a Sullustan was a typo. Furthermore, although not mentioned in the quest dialogue, examining Sithrin revealed him to be a sharpshooter. However, it should be noted that this was primarily due to game mechanics, as a result of Sithrin being placed under the randomized sharpshooter spawn template appearance.