Because you like Catherine Tramell in Basic Instinct
L is enigmatic, child-like, and one of the smartest people in the world. See them in Death Note.
Eren Jaeger will erase the Titans from this world until not a single one remains. See them in Attack on Titan.
Billionaire playboy by day and vigilante archer by night, Oliver Queen aims to rid Starling City of crime and atone for his past mistakes. See them in DC Extended Universe.
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.
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.
Usagi Tsukino may look like a lazy teen, but when Usagi conjures up her alter ego and calls her Sailor Scout team, no villain stands a chance. See them in Sailor Moon.
A 100-plus-year-old who looks like a dreamy teenager, Edward Cullen warns girls to avoid him, which makes them want him even more. See them in Twilight.
Joey Tribbiani's true passions in life are acting, sandwiches, football, sex, and asking ladies, "how you doing?" See them in Friends.
Leslie Knope can accomplish anything, literally anything, with a little grit and help from her office. See them in Parks and Recreation.
Jack Frost would rather crack a joke or throw a snowball than take anything seriously. See them in Rise of the Guardians.
A formerly timid caterpillar, Kurt Hummel is transforming into a glamorous, confident butterfly. See them in Glee.