a female that has usually never read the books and only saw the movie (couldve read the book and saw the movie but still the term "twilight bitch" is determined by the following behavior): acts like it's the biggest deal ever, thinks that Edward is the hottest thing since shaved pubes, buys thousands of dollars of twilight memorabilla, gets hair done like Bella in hopes of getting ass rammed by a rabinous vampire, and hates anyone who didn't see the movie, Twilight Bitch will soon over-populate the scenes (scene kids, scenesters, scenexcore, etc...) which overpopulated the emo kids after the popularity of Oli Sykes and Craig Mabbit rose to dangerous levels, which over-populated the goths which over-populated the punks, etc...
Izzy: eww have you seen this guy named Robert Pattinson, he's so ugly!
*4 years later*
Izzy: O.M.G!! Edward from Twilight is like so smexy!! he makes me have the BIGGEST orgasm.
Smart kid: thats the same person you said was ugly 4 years ago...
Izzy: NO ITS NOT!! cause Edward's a vampire and everyone knows vampires are the sexiest!
Smart kid: when did you decide that? when Twilight came out?
Other kid: come to think of it, every girl decided that vampires are sexy since Twilight came out.
Smart Kid: Izzy is such a Twilight Bitch