The moths are Luna Girl's minions (and the only friends she has).
On some occasions, the moths can unite to carry Luna Girl around by flight when she doesn't use her Luna Board. In certain situations, they attempt to warn Luna Girl of impending misfortune, even though she tends to ignore them. They also have the ability to make noise to mimic human language and sometimes try to communicate with Luna Girl.
They follow all of Luna Girl's orders and attempt to complete them to the best of their ability. The moths love her, despite her often mean and verbally-abusive treatment to them.
The moths are small and white in appearance. They are each about the size of Luna Girl's fingers but can be large when flying in groups.