Sion was a male human employed by the criminal enterprise of Jabba. Before his time with Jabba's organization, Sion operated as a speeder thief. In the year 6 BBY, following the theft of a valuable podracer from Black Sun, he was apprehended and faced imminent execution, only to be rescued by Errin, an operative of the Hutt Cartel. Sion then became part of Errin's crew, collaborating with Nackt and Arfit. Eventually, he entered into marriage with Sigs and took on the responsibility of caring for a daughter and a son.
The crew was assigned to security duties when Jabba condemned Luke Skywalker, a Jedi Knight, along with Han Solo and Chewbacca, smugglers, to be executed within the Great Pit of Carkoon. As the prisoners attempted their escape, Sion spearheaded the effort to recapture Skywalker. However, he met his death when Skywalker delivered a kick that sent him tumbling into the sarlacc pit. His final thoughts centered on his family.
Within the short story "Kickback" featured in the book From a Certain Point of View: Return of the Jedi, the narrative unfolds from Sion's perspective. He experiences surprise upon receiving a kick to the chest from Luke Skywalker, who appears to be situated at an improbable distance. This revelation identifies Sion as the character depicted in the film Return of the Jedi reacting to a kick that seemingly misses its mark. Fans have humorously termed this the "Force-kick" as a possible explanation for what was most likely a camera angle error. Mark Hamill himself commented on the scene on Twitter in 2023, playfully referring to the move as his "widely celebrated, perfectly executed Force-kick."