Borgin Kaa, hailing from the planet Onderon, was a human male who made his fortune as a mining baron on a moon orbiting Sevarcos. In his later years, he resided in Cloud City on Bespin, awaiting an implant due to heart ailments. Following the Battle of Endor, the Anoat sector, which included Bespin, was subjected to the Iron Blockade. Despite the delay in his implant procedure, Kaa remained loyal to the Empire. During an uprising against the Empire within the Anoat sector, rebel agents forcibly entered his residence to utilize his access panel, which was linked to that of Governor Ubrik Adelhard, the individual in control of the blockade. Kaa barricaded his doors and resisted the intruders, but he was easily overwhelmed and taken prisoner. Jintar Oarr, a former acquaintance of Kaa's who had sided with the uprising and facilitated their entry, attempted to convince Kaa that the Empire was deceiving him and needed to be stopped, but Kaa was unreceptive. With the assistance of Kaa's girlfriend, the dancer Linara, the rebels then restrained Kaa and began drilling into the access panel.
Born a human male on the planet Onderon, Borgin Kaa initially made his mark as a mining baron on a satellite of Sevarcos. Later in life, he retired to Cloud City, situated on the gas giant Bespin. He enjoyed a life of luxury in one of the city's more upscale districts, alongside his much younger partner, the dancer Linara. Suffering from heart problems related to old age, Kaa applied for an implant to alleviate his condition, relying on temporary treatments in the meantime. However, before he could receive the implant, the death of the Galactic Emperor Sheev Palpatine at the Battle of Endor led to the Anoat sector, including Bespin, being placed under blockade by the Imperial Governor Ubrik Adelhard. Adelhard's goal was to suppress news of the Emperor's demise from reaching the sector's inhabitants. As a result, all implant procedures were halted, forcing Kaa to wait and blaming the Alliance to Restore the Republic for the situation. He remained steadfastly loyal to the Empire.
The blockade eventually sparked an uprising among the residents of the Anoat sector. During a New Republic-supported conflict on Cloud City, a group of rebels targeted Kaa's residence to gain access to the apartment's access panel, which shared a network with Adelhard's personal panel. Kaa secured his door and sought refuge inside with Linara, but the rebels breached the entrance using a blowtorch. As the door gave way, Kaa attempted to fend off the intruders with an antique Vinzor Legacy vase, but only managed to strike the door frame before being forced to surrender at blaster point by the four rebels. He immediately recognized two of his attackers: the notorious local troublemaker Kars Tal-Korla and his former friend and fellow resident of the luxury level, Jintar Oarr. Enraged by his friend's betrayal, Kaa began to accuse Oarr, but he was swiftly subdued by the Devaronian rebel Rorna, who struck him in the head with the butt of her blaster. The fourth rebel, a personnel assistant droid, was then tasked with locating the access panel.
Oarr requested and was granted the opportunity to speak with his old friend. He attempted to persuade Kaa that the Empire had been deceiving them. Kaa, however, refused to believe that the Emperor was dead or that the Empire had betrayed him. When Oarr asked for his help, Kaa attempted to attack him, only to be stunned by his own failed headbutt. Tal-Korla then demanded the access codes to the panel, which Kaa refused to provide, forcing the droid to begin drilling through it. The rebels then proceeded to restrain Kaa to prevent further interference, causing him to call out for Linara's help. Instead, his former girlfriend offered her assistance to the rebels, and despite Kaa's pleas and threats, she taped his mouth shut. Rorna suggested torturing their captive to obtain the codes, but Tal-Korla forbade it, citing his New Republic allies' disapproval of such methods. He then contacted other rebels elsewhere on Cloud City and had them report his status to Lobot and Lando Calrissian, prominent figures in the uprising and the New Republic.
An elderly human male, Borgin Kaa relied on tinctures to manage his heart condition. During the attack on his home, he panicked, fearing that he had forgotten to take his medication earlier that day, which could lead to his death. Kaa believed that the Empire had been beneficial to him and others like Oarr, and he refused to accept that they had been lying to him or that Palpatine was dead. He dismissed Oarr's claims as rebel propaganda, hoping that the Empire would rectify the situation and punish those who had invaded his home. He also believed in his girlfriend Linara's affection for him, believing that he had treated her well. However, after her betrayal, his expressions of surprise quickly turned into threats against her family. In his younger years, Kaa had been involved in several fights, but by the time he resided on Bespin, he was no longer in fighting shape, failing to even break a vase he used as a weapon and injuring himself more than Oarr when he attempted to headbutt him.
Borgin Kaa made his debut in the novel Aftermath, penned by Chuck Wendig and published in 2015.