Because you like Amy Farrah Fowler in The Big Bang Theory
Optimus Prime is a shapeshifting sentient robot leading a team of robots to stop evil from taking over. See them in Transformers.
Ethan Hunt's mission, should he chose to accept it, is to save the world from impossible threats. See them in Mission: Impossible.
Romantic, tortured, and at times cruel, Heathcliff is an intense man. See them in Wuthering Heights.
When Jessica Jones is not throwing back drinks, she's taking down bad guys with her strength, detective skills, and foul-mouthed insults. See them in Marvel Cinematic Universe.
Light Yagami has a plan to make a better world, and morals won't stop him. See them in Death Note.
John Bender's interests include marijuana, fighting, and breaking the rules. See them in The Breakfast Club.
To cope with injustice, Connor finds meaning in his strict and unbreakable code of honor. See them in Assassin's Creed Series.
If there's any hope of resolving things peacefully, this proud ape leader will have to trust the humans. See them in Dawn of the Planet of the Apes.
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.
Hans Landa doesn't seem to have issues with Jews, but he hunts them because he's determined to do his job well. See them in Inglourious Basterds.