I gotta say the "fiction" comment is 100% acceptable.
Some people like Darth Vader in Star Wars. The cunt killed roughly 2 billion people as a form of torture on Princess Leia. What, waterboarding too passé? In the end he killed the emperor and said some nice shit to Luke... Nobody even gives a shit about the 2 billion people he killed for shits and giggles. The motherfucker has James Earl Jones' voice, so fuck off, he's untouchable!
Look at Jules from Pulp Fiction. The psycho kills people for a living. He killed "Flock of Seagulls" just to get Brett's attention. He fucking ate Brett's last meal on this earth (and drank his sprite!) and he fucking killed Brett for saying, "What!?" (well not exactly, but you gotta love all that "What" shit). But Jules decided to walk the earth like Caine, so all that shit is forgiven, plus, he's such a bad mother fucker, you gotta love him.
Hannibal Lector. He killed and served up a flautist to be unsuspectingly eaten by his friends at a dinner party because the hapless musician was a little off key!! OK, I can see that actually...
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Anyway, Hannibal is pretty much pure evil, but he was so fucking awesome, but which one, Anthony Hopkins or Mads Mikkelsen, fuck that's a hard choice!
Cersei Lannister, she fucks her brother, she's basically a psychopath (not as bad as Joffrey, but she fucking raised that cunt, so she gains evil points for that too), but fuck she was an awesome character!
Heath Ledger's Joker (or pretty much any Joker). The guy kills people quite literally for laughs. People love him (is it because Batman is so boring?)...
So yeah, in real life, those people would be despised by all. But it ain't real life, so there's no guilt in loving them.
Bottom line. Quinn is a bitch, but it's so much fun to "tame" her, to get under her skin and watch her façade melt. Who cares that she coerces girls into prostitution, sells drugs, pushes the mc out of the sorority naked, fucks (rapes
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) him secretly in front of the party, plays mind games with Maya and steals money from the HOTs for her own drug use. All that adds up to is she's the "Bad Girl", and you get to fuck her.
If the shit upsets people too much, there's always the Disney channel.