Catharsis Factor: MTV made the film for one reason, and one reason only — to let people watch one of the brats from My Super Sweet 16 get put through hell and eventually murdered for being such a annoying jerkass. And they delivered on all counts.
Derek is another huge one, on account of being the Plucky Comic Relief of the film and an all around Nice Guy even if he is more of a sidekick character.
Madison Penrose is an... interesting example. The entire fanbase despises her, but that's exactly why she's so popular. No other Alpha Bitch or Beta Bitch in the series has come close to snatching her crown as the Queen Bee of the franchise.
Sienna may count as well.
Part 3 also gives us Nico (popular for his hilarious Jerk Jock antics) and Ami (for being one of the more intelligent victims in the franchise)
The Scrappy: Courtney, for being incredibly obnoxious, providing no comic relief whatsoever, and getting Derek killed.
Nightmare Fuel: Nearly every single death scene is gruesomely over the top.
Take That, Scrappy!: Is basically "Take That, Scrappy!: The Movie" as it offers catharsis for those who want horrible things to happen to the spoiled brats that appear all too often on My Super Sweet Sixteen.
