Because you like Martha Jones in Doctor Who

Finn is the world's last human who's "all about" understanding right and wrong. See them in Adventure Time.

Level-headed Ian Gallagher may be focused on his goals, but he's got a mischievous side too. See them in Shameless.

Pro tip: the psych ward is not the best place to find a mentor like Lisa Rowe. See them in Girl, Interrupted.

An assassin with supernatural gifts, Corvo Attano is the last guy you should frame for murder. See them in Dishonored.

For somebody who won't answer questions, the enigmatic C.C. sure asks a lot of them. See them in Code Geass.

Those who stand against this singular super ninja are doomed to fail. See them in Ninja Gaiden.

Stuck somewhere between life and death, Talion is motivated by one thing only: vengeance. See them in Middle-earth: Shadow of Mordor.

Light Yagami has a plan to make a better world, and morals won't stop him. See them in Death Note.

Don't worry about this forensic scientist offing you unless you're a serial killer yourself. (You're not, right? Just checking.) See them in Dexter.

Don't mess with Mickey Milkovich unless you want to see the wrong side of one of his many guns. See them in Shameless.

Dominic Toretto lives his life "a quarter mile at a time", and he burns through those miles faster than anyone. See them in The Fast and the Furious.

You'll never get Alaska Young. And that's the whole point. See them in Looking for Alaska.