Rulue is Arle's rival and a powerful martial artist. She's madly in love with the main antagonist, Satan, which means she'll pretty much do anything he says. Most of those orders involve hassling Arle, which Rulue has no problem with given that she's jealous of Arle's magical powers.

I recommend those auditioning for Rulue to know or read up basic Japanese pronounciation due to all of her attacks being in Japanese.