Stuck Up Cunt Syndrome
A fictional disease attributed to bitchy girls as an attempt to explain why they are the way they are.

Commonly abbreviated as SUCS.

Bitchy girl: 
"I'm going to act like hot shit even though I'm not very attractive, then I'm going to get drunk and be a complete cunt to everyone that isn't a hot guy."

Observers: 
"Looks like she's got Stuck Up Cunt Syndrome."