Dena Yus was a biot engineered Human female through the financial backing of Marvid and Craitheus Qreph. She served as an operative at Lando Calrissian's asteroid processing plant situated on Sarnus within the Chiloon Rift, where the Qrephs plotted to defraud Calrissian of his facility. Upon realizing Calrissian's unwillingness to comply, Yus received orders to sabotage the plant, causing its ruin. The sabotage succeeded; however, Yus experienced remorse after witnessing the deaths of almost thirty thousand employees, including her clandestine lover, rather than the several hundred she had anticipated, though her loyalty to the Qrephs remained largely intact.
After aiding the Qrephs' employed Mandalorians in capturing Han Solo, the brothers abandoned her to perish aboard their mobile command center, the Ormni, by depriving her of the necessary feeding enzymes for survival. Luke Skywalker and Leia Organa Solo rescued her, and despite her confession of her terrible betrayal at the refinery, she was welcomed as an ally against the Qrephs, primarily so she could obtain her feeding enzymes at Base Prime, her place of origin.
Following the demise of the Qrephs and the obliteration of Base Prime, Yus was destined to face judgment before the Jedi Council on Shedu Maad for her transgressions.