Once upon a time, there was a great little web series called Making Fiends that turned into a swell TV series. Both versions told about the dynamic between Vendetta, an evil little girl that makes fiends, and Charlotte, who thinks Vendetta is her best friend despite the latter loathing her.
Here’s a video of the Halloween episode.
Alas, Nickelodeon cancelled the TV show after only one season. I’m glad I bough the DVD when it was available, as its now out of print and people are asking ridiculous amounts for it…