Rrrn, a resident of Mustafar and a Southern Mustafarian, existed during the Imperial Era. He was a member of the clan ruled by Father Kkkt. In the year 14 BBY, Rrrn participated in a scouting expedition tasked with examining a crashed object. However, upon reaching the site, the Mustafarian scouting party was attacked by Darth Vader, the Dark Lord of the Sith. Rrrn, surviving the assault alone, promptly informed Kkkt about the danger. Subsequently, Kkkt reached out to nearby Mustafarian clanholds, forging an alliance to oppose the Sith Lord and his forces.
During the Galactic Empire's reign, specifically in 14 BBY, Rrrn was a Southern Mustafarian belonging to the clan of Father Kkkt on the planet Mustafar. Kkkt, along with the rest of the clan, witnessed a fiery object plummeting onto Mustafar. Consequently, Kkkt dispatched Rrrn, alongside Sssp and Bbbl (both Northern Mustafarians), and another Southern Mustafarian, to investigate and provide a report. They journeyed to the supposed crash location on two lava fleas, with Rrrn as Sssp's passenger. Finding nothing, Sssp decided they should return to Kkkt. However, Bbbl noticed a shadowy figure nearby, who turned out to be Darth Vader, the Dark Lord of the Sith. Vader employed the Force to hurl a rock at Bbbl, sending the Mustafarian hurtling into the lava.
The Mustafarians then opened fire on Vader, but he used his lightsaber to deflect the blaster bolts, resulting in the death of one of the Mustafarians. Subsequently, the Sith Lord used the Force to lift Sssp into the air and strangle him. Rrrn then fled on the lava flea, returning to Kkkt to report the presence of the dark figure. Kkkt, concerned for the safety of his people, contacted the surrounding clanholds, forming a united front against Vader and his Imperial might.
Witnessing the demise of two fellow Mustafarians and Sssp being telekinetically manipulated by Darth Vader, Rrrn made the decision to escape to safety and alert Father Kkkt about the approaching danger.
Like other Mustafarians, Rrrn wore armor and a breath mask for protection from Mustafar's extreme heat. He also carried a Mustafarian blaster rifle and rode on the back of a lava flea during the scouting mission.
Rrrn's initial appearance was in Star Wars: Darth Vader, specifically the twenty-second issue of the 2017 comic series. Charles Soule wrote the issue, Giuseppe Camuncoli provided the illustrations, and Marvel Comics published it on October 17, 2018. His name was later revealed in the series' twenty-fourth issue, released on November 28 of that year.