She was one of BUMBA’s creations, but turned out to be such an irritating critter that she was thrown out.
She found an empty squat in the sky to live in and became lightning, but as a last pernicious act she took fire with her. A case of handling stolen goods with asbestos gloves.
Now she has to be given permission to take it down to Earth now and then for replenishment. This is always a mixed blessing as she can’t resist setting fire to things just for the hell of it.