Because you like Vivian Ward in Pretty Woman
Daria Morgendorffer is so defensive that she actively works to make people dislike her so that she don't feel bad when they do. See them in Daria.
Rukia Kuchiki is a cool and collected warrior who has trouble opening up to anyone. See them in Bleach.
Academics weren't his strong suit. Luckily, Jesse Pinkman's street smarts are a cut above the rest. See them in Breaking Bad.
While Cassie Ainsworth's head is always in the clouds, her heart is always in the right place. See them in Skins.
Walter White's knowledge of chemistry allows him to cook astoundingly pure meth, leading to a rapid – albeit tumultuous – rise in the criminal drug world. See them in Breaking Bad.
When the going gets tough, Rick Grimes gets tougher. It's a very useful trait when the world goes to hell. See them in The Walking Dead.
Daniel LaRusso is a Jersey kid in L.A. who is learning about karate and life from the mysterious Mr. Miyagi. See them in The Karate Kid.
A speed-loving daredevil who lives on the edge, Sonic is as brave as he is cocky. See them in Sonic the Hedgehog.
Rose Tyler may have not done too well in school, but she's certainly holding her own in space. See them in Doctor Who.
Hotheaded and arrogant, Kaneda is nevertheless fiercely protective of the biker gang he leads. See them in Akira.
Aang is already a master airbender and once he learns to manipulate water, earth, and fire, he'll be truly unbeatable. See them in Avatar: The Last Airbender.