Because you like John Locke in Lost
Jorah Mormont is loyal to his queen. And he's quite in love with her as well. See them in Game of Thrones.
Veronica Mars is a sarcastic private eye whose biggest mission is surviving high school. See them in Veronica Mars.
Dante Alighieri is a crusader fighting his way to absolution. See them in Dante's Inferno.
Riggan Thomson is a washed-up movie star running from his inner demons. Alas those inner demons look just like the superhero he used to play. See them in Birdman.
Ethan Hunt's mission, should he chose to accept it, is to save the world from impossible threats. See them in Mission: Impossible.
Anya Jenkins has a real harsh bark to go with her demonic bite. See them in Buffy the Vampire Slayer.
It's hard enough fighting a war. But it's worse for Commander Shepard, knowing no matter how hard you try, you can't save them all. See them in Mass Effect.
Inmate "Crazy Eyes" is a poetic soul with some big, expressive eyes. See them in Orange Is The New Black.
A ruthless militant, Raza will do anything to take down Tony Stark. See them in Marvel Cinematic Universe.
Simon Belmont is a vampire hunter bravely carrying on the family business. See them in Castlevania.
Sookie Stackhouse is a waitress who can read minds and break hearts. See them in True Blood.
Cynicism is his armor and words are his weapons, but what Tyrion Lannister would really like is some nice wine. See them in Game of Thrones.