I have to say, I don't envy the "Fraggle Rock" writers here. For two and a half seasons, we've learned that we can all get along and with a little effort and understanding, everyone can be friends. And now here we have an episode that has to say, "Welllllll, not everyone who says they're your friend is, kids. Matter of fact, in your life, you're probably going to have some relationships with so-called 'friends' that are downright poisonous. All we can do here is maybe help you recognize that most insidious kind of bullying early enough to stop it."
The realization that not everyone who says they're your friend has your best interests in mind is a pretty soul-crushing experience, isn't it? We all have someone in our past that we wonder why we ever hung out with them. Thankfully, none of them were magical jerkasses (I'm assuming; I don't know who you associated with in the dark, regretful times of your life, dear readers). Unfortunately, poor Wembly is not going to be able to say he never hung out with such an awful being.
The magical jerkass in question is -and this is brilliant- a Genie. Genies are very powerful supernatural beings that get trapped in bottles for unreasonably long periods of time. Once you let them out, they are so happy to be free, that they grant you wishes. Or, in the understandably less popular stories, they're so angry about being trapped for so long, that they wreck havoc. You can probably surmise from the title which approach this Genie takes.
Ah, but Genies are also in part defined by the certain rules they must obey. And this is why the metaphor in this episode is ingenious: the whole solution to this conflict hinges on Wembly realizing how dangerous this "friend" really is and being brave enough to wish he would stop. And better yet, we learn the Mean Genie has a sympathetic side and is willing to listen to reason.
As a very important aside, I have noticed that "Fraggle Rock" takes pains to humanize every antagonist. Yes, even in the episode that reinforces the lesson from this one, the pretty nightmare-fuel-erific "The Incredible Shrinking Mokey" (man, talk about a non-indicative title!) As a mater of fact, there is only one character, Wander McMooch, who can truly be classified as a straight-up villain. Tellingly, he's in a grand total of two episodes because he runs so contrary to the show's intent.
Anyway, I would be regretful indeed if I did not mention that this episode had one of the greatest, craziest musical numbers in the whole season. Mean Genie may be a magical jerkass, but he's got a pretty awesome kid-friendly psychedelic/punk rock thing going on.