Penelope Lang, is Betty's disgusting, snobbish, self-obsessed, near heartless queen bee rival, who thinks of herself as the most popular prima donna at her school. She is rich, spoiled, and often uses her popularity or wealth to undermine Betty's social standing, a plan that inevitably backfires. She is usually seen with two sidekicks named Megan and Sarah. She’s used to getting her own way — even if it means stepping all over other people. In fact, she enjoys getting her own way more if she has to step over other people to do so. In "Bracelet Yourself", she tampered with Betty's bracelet which is property of the Galactic Guardians and caused the Starcruiser to lose control. She also seems to not hate, but despise Betty enough to be violent, for in "Pre-Teen Queen of Outerspace", she attempts to kill Betty and her friends, though she thinks it is just a dream, and in "Mirror of Morgana", she kicks Betty in the face. Being Betty's rival, she also dislikes Noah just about as much as she dislikes Betty. In season three, she is occasionally seen with her grandmother Petunia, who is just about as snobbish as she is.Though she has come close to discovering the existence of the Galactic Guardians (having stolen Betty's bracelet in "Bracelet Yourself", accidentally teleported into Galactic Guardian HQ in "No Space Like Home", being given a note from her future self in "The Future is Now", and even having tampered with and read out of Betty's own "captain's log"), she quickly dismisses all of the evidence.
In "The Future is Now", Penelope, while not a Galactic Guardian herself, is freeloading with the remnants of the Galactic Guardians. However, she provides the opportunity for Betty and Noah to steal the time machine back from Maximus and return to the past.
The alien bee people of Droneopolis apparently consider Penelope to be the "Most Evil Female" in the cosmos to the point they kidnap her and create a hybrid clone of Penelope to be their Queen, Queen Penelobee.