Because you like David Wooderson in Dazed and Confused
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.
When their organization was infiltrated by evil HYDRA, who was the one guy Captain America trusted? A former soldier with kickass wings named Sam Wilson. See them in Marvel Cinematic Universe.
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.
Morticia Addams hates anything bright and cheery and loves all things ghoulish, ghastly, and violent. See them in The Addams Family.
Fiery and adventurous, Amy Pond is the sort of woman you'd want by your side on a journey through time and space. See them in Doctor Who.
When you live your life in public, like Mima Kirigoe, it's hard to know who you really are. See them in Perfect Blue.
Most kids hope for a car for their 16th birthday, but Mia Thermopolis' present is a country to rule. See them in The Princess Diaries.
Melinda May is a woman of few words and many talents. Most of them martial. See them in Marvel Cinematic Universe.
Genetically and cybernetically enhanced, Gamora was trained from birth to be one of the deadliest women in the galaxy. See them in Marvel Cinematic Universe.
Clary Fray's philosophy: dive into the supernatural underworld first and ask questions later. See them in City of Bones.
A natural leader, Clarke Griffin dispenses both justice and mercy, and she does it all while being selflessly humble. See them in The 100.