Luida is the leader of the floating colony.

In Trigun Maximum, she and other colony members took Vash in after finding him lost in the desert without his left arm, which had already been cut off by Knives during their first confrontation. After discovering their origin and everything that was going on, Luida and the colony joined forces with Vash in an attempt to defeat Knives and stop his extermination plan. But after so many defeats, Vash decided to take matters into his own hands. Respecting his decision, the colony provided all of his equipment, from the iconic red coat to the prosthesis on his left arm. Even after that decision, she is always willing to help Vash with whatever it takes.

In Trigun Stampede the story is basically the same, but now Luida is studying the power of Plants to fertilize the soil of No Man's Land.