Well, her name isn’t actually Luna, she just gave herself that nickname because she is Terra’s #1 fan. Like for real, she runs the fan club and everything. And follows her around. And sneaks into very exclusive areas just to be seen with her. She gets apprehended by security very often, and the other ICS members call her a stalker, but honestly Terra doesn’t mind and talks to Luna as if she’s an old friend.
Her real name is Selena Tolvaj and she thinks very highly of herself and acts bigger than she actually is. People call her a Pastel Edgelord(tm), and by people I mean herself. She dabbles in kleptomania, and those tendencies do not exclude Terra.