Kardue'sai'Malloc, a cunning Devaronian, once held the rank of a brutal army captain on his planet of origin, Devaron. To escape his dark former existence, which had placed a massive bounty on his head throughout the galaxy, he went underground, adopting the name Labria. Posing as a significant informant, Kardue'sai'Malloc frequented Chalmun's Spaceport Cantina located in the Mos Eisley spaceport on the world of Tatooine, spending much of his time there.
During the year 0 BBY, he was present within the cantina when Garindan ezz Zavor, a Kubaz spy, entered, searching for a pair of droids sought by the Galactic Empire. Later, he shared a drink of Merenzane Gold with two other individuals when Obi-Wan Kenobi, a Jedi Master, became embroiled in a dispute with Cornelius Evazan, a Doctor, and Ponda Baba at the bar. Subsequently, Zavor requested Kardue'sai'Malloc's assistance in finding employment, leading the Devaronian to connect him with an assassination assignment for the Ketton named Derrida.

Hailing from the jungle world of Devaron, Kardue'sai'Malloc was a Devaronian who began his career as an army captain. By the time 0 BBY arrived, he was a fugitive from justice, attempting to outrun a past filled with wickedness that had resulted in one of the highest bounties in the galaxy being placed on his head for the terrible acts he had committed. He adopted the alias Labria and sought refuge in the Mos Eisley spaceport on Tatooine, endeavoring to present himself as a key informant, even though he was a remarkably poor spy. During the Galactic Civil War fought between the Galactic Empire and the Alliance to Restore the Republic, he spent much of his time at Chalmun's Spaceport Cantina, enjoying alcoholic beverages in the company of other disreputable characters.
During this period, he engaged in a game of sabacc with Nabrun Leids, a Morseerian, and Muftak, a Talz, in one of the cantina's booths. This occurred while Bossk'wassak'Cradossk, a bounty hunter, was searching the establishment for the runaway Imperial astromech droid known as 261. One morning in 0 BBY, Kardue'sai'Malloc was again present in the cantina, concealing his pointed smile and idly tapping his fingers to the rhythm of music that only he could perceive. It was then that Garindan ezz Zavor, a Kubaz informant, entered, seeking two droids that the Empire was actively trying to locate. After Zavor departed to continue his search elsewhere, the Devaronian convened with Ketwol, a Pacithhip, and Arleil Schous, a Defel, inside the cantina. This group shared a jigger of Merenzane Gold, an alcoholic drink, at a table that was situated next to Dice Ibegon, a Lamproid, when a brawl erupted at the bar. The fight involved Ponda Baba and Cornelius Evazan, both criminals and Doctor, against Obi-Wan Kenobi, who was a Jedi Master. During the altercation, Luke Skywalker, a local moisture farmer, was thrown into the table where Kardue'sai'Malloc and his companions were seated.

Kardue'sai'Malloc remained in the cantina when Zavor returned later, seeking another drink. While the Kubaz awaited payment for a completed task, the two discussed Figrin D'an and the Modal Nodes, the cantina's house band. The Devaronian expressed admiration for the band, but the Kubaz criticized them for a perceived lack of high musical tones. Kardue'sai'Malloc retorted that Zavor possessed no understanding of music. Upon learning that he would not receive his payment, the Kubaz's snout drooped. Kardue'sai'Malloc inquired if something was amiss. Zavor informed the Devaronian that he needed a quick job that day. With renewed interest in the Kubaz, Kardue'sai'Malloc mentioned that Derrida, a Ketton, required an accomplice for an assassination scheduled for that night.
When the Kubaz questioned why Kardue'sai'Malloc had not undertaken the job himself, the Devaronian responded with laughter, stating that it involved too much effort. However, when Zavor offered half a credit, Kardue'sai'Malloc clarified that no one else would accept the job because it involved acting against the Alliance to Restore the Republic. Zavor accepted the assignment, and Kardue'sai'Malloc contacted Derrida via his datapad, informing the Kubaz that she would provide him with the necessary coordinates. He then probed Zavor about the numerous rumors surrounding the Kubaz, chuckling and returning the half credit in exchange for an answer when Zavor gestured for it. The Kubaz simply stated that he was far from home before departing.

Kardue'sai'Malloc possessed a cunning, cruel, and malevolent nature. He viewed different employers as largely interchangeable when accepting assignments and showed little concern for aligning himself with either the Empire or the Alliance during the war. He believed that this was a concern specific to humans. While he deemed working with Derrida on an Imperial assassination to be excessively laborious, he shared information about the job with Zavor, only revealing its controversial nature after receiving half a credit. Once Zavor accepted the job, Kardue'sai'Malloc regarded the spy with a newfound curiosity. Having heard numerous rumors about the Kubaz, the Devaronian was willing to return the half credit to learn what Zavor considered to be the truth.
Kardue'sai'Malloc held a favorable opinion of the music performed by Figrin D'an and the Modal Nodes, and he criticized Zavor's musical knowledge when the Kubaz suggested that the band's performance lacked higher tones. Zavor did not believe that the Devaronian could comprehend him or interpret even a fraction of his body language. However, he did notice the Kubaz's reaction upon learning that he would not be paid. When in thought, Kardue'sai'Malloc audibly ground his pointed teeth. He had red skin and brown eyes.
Kardue'sai'Malloc possessed average speed, strength, intelligence, and combat skills. However, his diplomatic abilities were below average, and he was a poor spy. He was not Force-sensitive.
When at the cantina, Kardue'sai'Malloc wore an ensemble that included a brown scarf, a black cape, a gray shirt, silver gauntlets, and a black belt. He also possessed black gloves, black pants, and black boots. He utilized a datapad and weapons such as a DL-18 blaster pistol and a DL-44 heavy blaster pistol.

Penny McCarthy played Kardue'sai'Malloc in Star Wars: Episode IV A New Hope, a film from the original trilogy that premiered on May 25, 1977. His scenes were filmed during additional photography in post-production, where they created extra footage for the cantina scene on a sound stage at Dovington's Hollywood studio between January 24 and 25, 1977.
Rick Baker, a makeup artist, created the latex mask used for Kardue'sai'Malloc for an unreleased early 1970s John Landis film called "I was a Teenage Vampire." It was later used in "The Thing in the Attic," a Halloween show by Bob Burns in 1974. By the time it appeared in Star Wars, they had changed the mask by shortening the horns and removing a beard. On set, the character was referred to as "Louie," "the Devil," and "Devil Guy." The mask was later given to Burns and his wife, Kathy Burns. They had Tom Spina Designs partially restore it for display because it had become distorted.
In current Star Wars canon, the character's names were first used in the mobile card game Star Wars: Force Collection, which launched in 2013. Even though Force Collection's launch came before the Star Wars canon reset of 2014, Leland Chee of the Lucasfilm Story Group confirmed that the game was updated to match canon. In Star Wars Legends continuity, the character was initially identified as just "Labria" in Galaxy Guide 1: A New Hope, a 1989 supplement by Grant S. Boucher for West End Games' Star Wars: The Roleplaying Game. The name "Kardue'sai'Malloc" was introduced in "Empire Blues: The Devaronian's Tale," a short story by Daniel Keys Moran in the 1995 anthology Tales from the Mos Eisley Cantina.

Kardue'sai'Malloc is in Maggie Simpson in "The Force Awakens From Its Nap", a non-canon The Simpsons short released on May 4, 2021. In the short, the Devaronian is seen during the credits, talking to a patron next to Homer Simpson at the Mos Eisley cantina's bar. The character also appeared in "Tatooine Rhapsody," a short film in the Star Wars: Visions series released on September 22, 2021, with ambiguous canon status. In the film, the Devaronian is at the bar in the Mos Eisley cantina while other patrons watch Star Waver's performance on handheld viewscreens. Kardue'sai'Malloc is also seen listening to the Modal Nodes at the cantina when rebel agent Kori Zaran passes through while trying to reach Echo Base on Hoth in the 2023 non-canon LEGO book LEGO Star Wars Galaxy Mission, by Julia March with LEGO models by Rod Gillies.