Sienn'rha, a Twi'lek female, forged a friendship with Oola and chose to align herself with the Rebellion during the period of the Galactic Civil War.
Much like Oola, Sienn'rha's early life took a dark turn when she was abducted and subjected to slavery at the hands of Bib Fortuna while still a young girl. Fortuna's intentions were to mold them into dancers destined for the court of Jabba Desilijic Tiure. During their transport to Jabba's Palace, Jerris Rudd concealed the two captives, but their hiding place was later discovered by Luke Skywalker. Skywalker attempted to orchestrate their escape, but Oola harbored reservations. Rudd then intervened, initiating a confrontation. Skywalker skillfully deflected Rudd's blaster fire, resulting in Rudd's death and creating an opportunity for the dancers to break free. Oola, in a selfless act, diverted the attention of the newly arrived Fortuna and urged Sienn'rha to flee, driven by her realization of Fortuna's malevolence and a desire to protect her friend.
Later, she made her way back to Ryloth, holding a lasting gratitude towards the Rebel Alliance for their role in her liberation. When Rogue Squadron undertook a mission to Ryloth to procure Ryll kor, Sienn'rha was among the dancers providing entertainment for the pilots. She extended an invitation to Wedge Antilles for a private dance, an offer that he respectfully declined.
Sienn was a common name for Twi'lek females, translating to maiden in the Twi'leki language.
Kathy Tyers conceived the character of Sienn for Oola's story featured in Tales from Jabba's Palace. Subsequently, in that year, Michael A. Stackpole included a brief cameo of her in X-Wing: The Krytos Trap, where he revealed her full Twi'leki name, Sienn'rha.
An inaccuracy appears in Sienn's entry within The Complete Star Wars Encyclopedia, which incorrectly states that she was presented to Jabba the Hutt alongside Oola, and subsequently rescued from Jabba's Palace by Luke Skywalker. Contradicting this, all other sources, including Oola's own entry in the same encyclopedia, assert that Skywalker liberated her in Mos Eisley before she was ever taken to Jabba.