Lillias was a female Nezu whose village was destroyed during an artificial asteroid attack caused by the Etanians, who wished to conquer the Nezu. She was rescued by Neelix, who was part of a rescue mission to save Dr. Vatm, a Nezu scientist who had evidence of the plot and that Dr. Sklar was a traitor.
They used a carriage that was tethered to a space station. During the trip upward, Lillias disliked how Tuvok treated Neelix, and informed him he should respect Neelix. After being beamed to USS Voyager, she was reunited with her family including her sister Halla. (VOY: "Rise")