Because you like Todd Anderson in Dead Poets Society
Wei Shen is an undercover cop on a mission for justice (or at least vengeance). See them in Sleeping Dogs.
Red doesn't like to explain herself. She wants her work to do the talking. See them in Transistor.
Juliet Starling is a cheerleader by day, gleefully unhinged zombie killer by night. See them in Lollipop Chainsaw.
Experiment 626 was designed for one thing: to destroy everything he touches. See them in Lilo & Stich.
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.
It’s a shame that the Seven Kingdoms doesn’t allow a woman to rule. The scheming, focused Cersei Lannister would do a far better job than either of her sons. See them in Game of Thrones.
The ever-cheerful Tonks can change her appearance at will, but she can't seem to get rid of her clumsiness. See them in Harry Potter Series.
Aslan represents everything good and just, he's just not super reliable. See them in The Chronicles of Narnia.
Just call Jeff Lebowski The Dude. Or His Dudeness, Duder, or El Duderino if you're not into that whole brevity thing. See them in The Big Lebowski.
Despite the dissolution of his state, Prussia hangs on – mooching off his younger brother Germany and reading comics. See them in Axis Powers Hetalia.
If it were up to her, Merida would spend her days practicing archery and swordfighting, riding her horse, and exploring the Highlands. See them in Brave.
With great power comes great responsibility, but Peter Parker always seems to get the short end of that bargain. See them in Marvel Cinematic Universe.