Ktriss was a Hssiss dragon of the female persuasion, serving as the cherished companion of Great Bogga. Bogga was a Hutt crime lord who held dominion over the Stenness star system. Often seen by her master's side, Ktriss acted as the Hutt's personal executioner. Originating from Lake Natth located on the planet Ambria within the Stenness Node, Ktriss possessed a natural ability akin to others of her species, allowing her to influence the dark side of the Force. In the year 3999 BBY, Ktriss showcased her deadly killing prowess for Great Bogga within his court situated on the moon of Vo Dasha. Finhead Stonebone, a pirate captain, alongside his gang, were presented before the Hutt to answer for their transgressions. Stonebone's refusal of Bogga's initial offer of restitution led to Ktriss being unleashed upon Roko, one of Stonebone's crew members, who was devoured in front of his comrades.

A female Hssiss, Ktriss belonged to a species of dragon that originated from Lake Natth on the planet Ambria, situated in the Inner Rim region of the Stenness Node. The creatures inhabiting that lake were deeply connected with the dark side of the Force, an effect caused by a powerful Jedi Master who had trapped the planet's darkness within it. As such, Ktriss had a subtle ability to manipulate the Force, utilizing its power to confuse the minds of those she hunted.
While still young, Ktriss was discovered by a traveling Hutt known as Great Bogga, who reigned as the crime lord of the Stenness star system, where Ambria was located. Intrigued by the young Hssiss and her species, Bogga captured several dragons with the intent of taking them off-world. All were sold on the black market to colleagues and darksiders alike, with the exception of Ktriss, whom the Hutt claimed as his own. Ktriss was brought to his stronghold on the moon of Vo Dasha, where she served as the Hutt's personal security enforcer. As time went on, Ktriss grew significantly in size and ferocity, becoming a formidable presence at Great Bogga's side.
In 3999 BBY, some members of Bogga's enforcer gang were unsuccessful in stealing a cache of precious Adegan crystals from a family of travelers passing through the Stenness Hyperspace Terminal. Ktriss was present when only the gang's leader, Gudb, returned in disgrace, a sight that made her drool. Under the threat of Ktriss' wrath, Gudb was forced to pursue the crystals' owners to Ambria, the dragon's homeworld. Bogga accompanied his minions, leaving Ktriss behind, but ultimately returned to Vo Dasha empty-handed, having been defeated by the Jedi Knights who resided there.

Around the same period, Bogga's enforcer gang apprehended ore thieves for engaging in acts of piracy against several of the Hutt's allies. Ktriss lay beside her master as Finhead Stonebone, a pirate captain and the leader of the gang, was brought before them. As compensation for Stonebone's crimes, Bogga instructed the pirate to travel to Ambria and retrieve the Adegan crystals from the Jedi who had previously defeated the Hutt and his minions. However, Stonebone refused to involve himself in any act that required taking up arms against Knights of the Republic and remained defiant before the Hutt.
Incensed by Stonebone's defiance, the Hutt resolved to demonstrate the consequences of disobeying Great Bogga to the pirate. Ktriss was summoned into action and unleashed upon Roko, Stonebone's first crewmate, a humanoid. Ktriss used the dark side of the Force to temporarily cloud the pirate's mind, rendering Roko immobile as she descended upon him, much to the horror of Stonebone and his gang. Ktriss devoured her victim entirely, leaving only a bloody mess in Roko's place. Witnessing his comrade's death at the hands of Ktriss was enough to compel Stonebone into service, much to the satisfaction of Great Bogga the Hutt.

Ktriss possessed green scales, black eyes, a lengthy and robust tail, and spiked protrusions arranged in two rows along her back. She was of considerable size when on all fours, and when she stood on her hind legs, Ktriss towered over an average adult humanoid. She also had lengthy, sharp teeth and massive talons. She was responsive to the instructions of her master, Great Bogga, who believed that Ktriss was capable of devouring his lead enforcer, Gudb, in a single bite. Ktriss indeed showed a hunger for Gudb, gnashing her teeth and salivating heavily in the gangster's presence. However, Gudb believed that his own pet gorm-worm, Skritch, was more than capable of defeating Ktriss. The dragon was loyal to her master and frequently accompanied him. The fear of Ktriss' abilities was sufficient to make Captain Stonebone reconsider the offer presented by Bogga.
Ktriss employed her large teeth and claws to devour her prey. She was capable of overpowering adult humanoids, as demonstrated by her defeat of the space pirate Roko. Upon Bogga's command to demonstrate her ferocity, the Hssiss immediately attacked Roko, tearing him to shreds in front of his comrades. Ktriss was also Force-sensitive and utilized the power of the dark side while hunting to temporarily confuse her victims, making it easier for her to subdue them.
Ktriss made her debut in the fourth issue of Tom Veitch's Tales of the Jedi story arc within the Tales of the Jedi comic series. Ktriss is also featured in the audio rendition by John Whitman, which is based on Veitch's script. Further details about her backstory were later established in 2001's The Dark Side Sourcebook, a supplement to the Star Wars Roleplaying Game published by Wizards of the Coast.