Lahka Khai, a Human female hailing from the planet Kesh, entered into matrimony with the Sith Saber Gavar Khai, and from their union came one offspring, Vestara. Unlike her spouse and child, Lahka did not possess any Force-sensitive abilities. In the year 41 ABY, Vestara was selected to become the Sith apprentice of Lady Rhea, which led to her departure from her family to reside within the Sith Temple. At a later point, Vestara was dispatched on a mission to face the Jedi Luke Skywalker; during this time, Lahka Khai maintained good health, though she felt the absence of her daughter. Lahka was in Gavar's presence when the dark side entity known as Abeloth made her arrival on Kesh in 44 ABY, following Abeloth's proposition of an alliance with the Sith with the goal of defeating the Jedi. However, that very evening, Abeloth initiated an attack on the city of Tahv, resulting in its devastation and the death of numerous inhabitants, Lahka among them.
Born on the Wild Space world of Kesh, Lahka Khai was a female of the Human species. Despite lacking any Force-sensitive abilities, she married Gavar Khai, a Sith Saber and a member of the Lost Tribe of Sith. These Sith were descendants of a group of Sith whose starship, the Omen, had crashed on the planet in 5000 BBY during the Great Hyperspace War. Together, the Khais made their home in a private estate located on Kesh.
Lahka and Gavar welcomed one daughter into the world in 27.5 ABY, and they named her Vestara. Vestara commenced her training in the ways of the Sith. Shortly after Ship, a Sith Meditation Sphere, arrived on Kesh in 41 ABY, she was summoned to meet with the Circle of Lords in the Circle Chambers of Kesh's capital city, Tahv. Both Gavar and Vestara were concerned that she might be in trouble, and Lahka sensed that something was amiss, but she understood that Sith affairs were not her concern. However, during the meeting, Vestara was chosen to become the apprentice of Lady Rhea. To begin her training, Vestara had to relocate from her family's home and reside within the Sith Temple situated in the nearby Takara Mountains.
In 43.5 ABY, Vestara was selected to be a member of the Sith strike team tasked with confronting the Jedi Luke and Ben Skywalker. She emerged as the sole survivor of the mission and proceeded to recruit a group of dark side Nightsisters from Dathomir to support the Tribe's cause. Gavar also embarked on a mission to locate Vestara and then feign an alliance with the Jedi in order to attack the dark side entity Abeloth. Throughout this period, Lahka Khai remained in good health. She felt the absence of her daughter but also took great pride in Vestara's accomplishments.
In 44 ABY, Gavar returned to Kesh alongside Abeloth, who, following multiple encounters involving herself, the Sith, and the Jedi, had proposed an alliance with the Sith to defeat the Jedi. He was able to spend some time with Lahka at their estate for a few days. Lahka then accompanied Gavar and the majority of the Sith in the Tribe to welcome Abeloth's arrival planetside at the Tahv spaceport. Later that evening Lahka returned to their estate while Gavar attended a masquerade for Abeloth to which Lahka had not been invited. Gavar spent the night on his ChaseMaster frigate, the Black Wave, rather than returning home; and in the night Abeloth unleashed a powerful attack on the city, leaving much of Tahv in ruins and destroying many of its inhabitants. Despite the fact that Lahka was among those who died, Gavar chose to betray the Tribe and ally with Abeloth.
Lahka possessed intelligence, patience, and a talent for keeping secrets—qualities that compensated for her lack of Force-sensitivity in Gavar's estimation. She also had the ability to discern some of Gavar's emotions. Lahka's understanding of the affairs of the Lost Tribe of Sith was incomplete, but she recognized that it was not her place to interfere in their matters. Consequently, she refrained from questioning her husband and daughter when they appeared troubled by Vestara's summons to the Circle Chambers. She missed her daughter when Vestara embarked on a mission off-planet with the intention of eliminating the Skywalkers, but she took pride in Vestara's achievements. When Gavar informed her of Vestara's developing relationship with Ben Skywalker, Lahka suggested that Ben could potentially become a valuable asset to the Tribe and their family if Vestara could sway him, and when Gavar responded with his fear that Ben might sway her, Lahka stated her faith that Vestara would never betray her family, the Tribe, or the dark side.
Lahka had a fondness for the Sith Victory flower, and she enjoyed crushing them during Abeloth's celebration to savor their fragrance. She possessed exceptional beauty—as attractive as the native Keshiri women—and had a gentle smile.
The character of Lahka Khai was brought to life by author Christie Golden for her inaugural Star Wars novel, Fate of the Jedi: Omen, which served as the second installment in the nine-novel Fate of the Jedi series, released on July 23, 2009. She was briefly mentioned in the fifth and sixth novels, Fate of the Jedi: Allies and Fate of the Jedi: Vortex, respectively, before making an appearance in 2011's Fate of the Jedi: Ascension, the eighth novel of the series.