Because you like Leonard Hofstadter in The Big Bang Theory

Dr. Gordon Freeman is a brilliant physicist is a quiet hero. And given all the violent aliens, he better be. See them in Half-Life.

Her interests include martial arts, interrogation, and hacking. Natasha Romanoff is the ultimate spy. See them in Marvel Cinematic Universe.

Rhodes has to trust his conscience to guide him through a political struggle that could change the very shape of modern warfare. See them in Marvel Cinematic Universe.

Lyra Belacqua is prone to getting in trouble, but she's also clever enough to get out of it. Most of the time. See them in The Golden Compass.

Rukia Kuchiki is a cool and collected warrior who has trouble opening up to anyone. See them in Bleach.

Think you grew up fast? At 12, Mathilda is an aspiring assassin eager to avenge her family's murder. See them in Leon: The Professional.

Arthur Dent is an incredibly normal man on an incredibly abnormal adventure. See them in The Hitchhiker's Guide to the Galaxy.

George Costanza is short, stocky, bald, neurotic, and the self-proclaimed "king of the idiots." See them in Seinfeld.

GLaDOS will supply the food when you get together: a delicious cake. Of course, it could just be a trap so she can kill you. It’s hard to say. See them in Portal Series.

Carl Fredricksen is a crotchety old man who may just have it in him to take one last, great adventure. See them in Up.

Marv is a brutish but principled thug who'd be right at home on an ancient battlefield. See them in Sin City.

There are certain souls the surprisingly sensitive Death would rather not reap. See them in The Book Thief.