Because you like Jack Harkness in Doctor Who
Bella Swan thinks of it as her job to help her parents and protect her friends, even though it often ends up the other way around. See them in Twilight.
Tracy Turnblad's got rhythm, and she's determined to share her dance moves with the world. See them in Hairspray.
The adventurous daughter of Port Royal's governor, Elizabeth Swann would rather conspire with pirates than sit pretty in her corset. See them in Pirates of the Caribbean: the Curse of the Black Pearl.
Damon Salvatore used to miss being human. Now he can't think of anything more miserable. See them in The Vampire Diaries.
Smart, sarcastic, and loyal, Stiles Stilinski doesn't just want to be the sidekick in someone else's life. See them in Teen Wolf.
Rukia Kuchiki is a cool and collected warrior who has trouble opening up to anyone. See them in Bleach.
Bart Simpson is an aspiring juvenile delinquent who doesn't want you to have a cow, man! See them in The Simpsons.
A girl who grew up on stories, Meggie Folchart is as loyal and intrepid as one of her fictional heroines. See them in Inkheart.
Those who stand against this singular super ninja are doomed to fail. See them in Ninja Gaiden.
Po is a clumsy, friendly panda who likes to take it easy. But now he's expected to save the world? See them in Kung Fu Panda.
Light Yagami has a plan to make a better world, and morals won't stop him. See them in Death Note.