Lord Keto, a male Human, held the position of ruler over the Empress Teta system alongside his sister, Magda Keto. This occurred in the years preceding the Great Sith War. Satal, Keto's son, and Aleema, Magda's daughter, were the designated heirs to the throne of the system. Keto's control over the system was shared with commercial entities involved in carbonite mining within the Empress Teta system, often engaging in clandestine agreements with mining executives. However, his lack of attention towards his heirs led them to establish a darksider cult known as the Krath. In 3997 BBY, Satal and Aleema resolved to employ dark side Sith magic to overthrow Lord Keto and his sister. The Krath launched their assault while Keto and his sister were conducting an inspection of a Tetan carbonite smelter in orbit above the planet Empress Teta. Despite Keto's orders for his Royal Protectors to intervene, they were decimated by Satal and Aleema's magic. Defenseless, Keto was captured by the rebellious heirs and frozen in carbonite along with Magda, resulting in his death. His carbonite-encased body was then displayed as an ornament on the walls of the Iron Citadel, which had been his palace but was now the headquarters of Satal and Aleema in the capital city of Cinnagar on Empress Teta.
Before the Great Sith War, Lord Keto, a male Human, and his sister, Magda Keto, jointly governed the Empress Teta system. The Ketos were descendants of Empress Teta, a female warrior who had unified the seven worlds of the then-Koros system almost a millennium prior. Keto eventually fathered a son named Satal, who, along with Aleema, Magda Keto's daughter, was in line to inherit the Tetan throne. The Ketos were compelled to share their authority with commercial entities that managed carbonite mining operations within the system, often engaging in secret deals with the mining executives. In a particular year, Lord Keto and his sister conducted their annual inspection of a Tetan carbonite smelter positioned above the planet Empress Teta. They were greeted by Bearus, the chairman of the system's Carbonite Guild. During their exchange, news arrived that a royal ship carrying Satal and Aleema Keto, their tutor Korus, and four others had docked at the smelter. Keto and the others were displeased by the unexpected arrival of Korus and the students, unaware of their reasons for coming to the smelter. Satal and Aleema had become skilled in dark side Sith magic and, fueled by Lord Keto's neglect, had established a darksider organization called the Krath, with the goal of seizing control of the Empress Teta system.
Lord Keto and Bearus resumed the inspection, with the Emperor expressing satisfaction with the proceedings. As the inspection continued, Korus and his students, including Satal and Aleema, joined them. Keto reprimanded Korus for bringing the students during a royal inspection, deeming it an unacceptable breach of protocol, but Korus remained silent. Satal intervened, urging his father not to scold Korus and instructing the tutor to reveal what Aleema had done to his tongue. Korus complied, revealing that Aleema had used the dark side to transform his tongue into an Adegan eel. The Ketos were horrified, and Bearus attempted to summon security. However, Aleema transformed the communications console into a womp rat. Lord Keto called upon his Royal Protectors to arrest the young Tetan heirs, but Aleema countered by turning the guards' swords into snake-like monsters that strangled them. A terrified Lord Keto attempted to reassure the guards that the snakes were not real, but his efforts were futile. With no protection remaining, Keto ordered his son to stand down, but Satal refused. Satal and Aleema informed the angered Keto that they had already legally assumed control of the Empress Teta system. The heirs then led the now-former rulers of the Tetan worlds to a vat of molten carbonite, where they immersed both Lord Keto and Magda Keto, freezing them in carbonite and causing their deaths. With their coup complete, Satal and Aleema displayed the carbonite-encased bodies of Lord Keto and Magda Keto on the walls of their palace, the Iron Citadel, where the former rulers served as decorations.
Satal, his son, described Lord Keto as "pompous and cold," while his niece Aleema referred to him as a "windbag." In return, Keto harbored resentment toward his son and niece, considering them spoiled. During his family's reign over the Empress Teta system, Keto was willing to employ ruthless tactics, including using torture droids to maintain control of the populace and engaging in clandestine deals with the carbonite smelting companies operating within the system. Keto prioritized his duties as the ruler of the system over his responsibilities as a father to Satal, which fueled anger and hatred within his son. He was quick to react harshly when angered, as demonstrated by his berating of Korus for interrupting his royal inspection of the carbonite smelting plant. His anger eventually gave way to fear when the Krath began using the dark side to attack his Royal Protectors.
Lord Keto made his debut in Star Wars: Tales of the Jedi - Dark Lords of the Sith, a story arc within the Star Wars: Tales of the Jedi comic book series, authored by Kevin J. Anderson and Tom Veitch, and released in late 1994 to early 1995. Keto's first and only appearance was in the first issue of the arc, where he met his demise. He was later mentioned in the second and third issues of Dark Lords of the Sith. In his sole appearance in the arc, he was illustrated by Chris Gossett. Keto also featured in the Dark Lords of the Sith audio adaptation.
In the Dark Lords of the Sith audio adaptation, Lord Keto's sister Magda is absent; therefore, Keto is presented as being the only member of the Tetan Monarchy at the inspection of the carbonite smelter, and Magda's lines in the comic are attributed to him.