Because you like Christopher John Francis Boone in The Curious Incident of the Dog in the Night-Time
He's a troubled insomniac in search of a moment to rest and a meaning to his existence. See them in Fight Club.
An agile and powerful swordswoman, Saber is a dignified warrior down to her bones. See them in Fate/Stay Night.
How is angel Aziraphale supposed to stop the apocalypse when Hell's forces misplaced the Antichrist somewhere? See them in Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch.
An opportunistic fugitive-turned-bounty-hunter, Faye Valentine uses both grit and her good looks to get ahead. See them in Cowboy Bebop.
Strong-willed Norah Silverberg isn't willing to be the goody bag at anyone's pity party. See them in Nick and Norah's Infinite Playlist.
Rogue's touch is literally deadly, and she's trying to learn from the older mutants how to manager her powers. See them in X-Men Series.
Leone Montana is a fearless hitman with a surprisingly sensitive side. See them in Leon: The Professional.
Twisted and seemingly soulless, Bellatrix Lestrange finds joy in making others suffer. See them in Harry Potter Series.
Georgina Sparks uses beauty, brains, and power to always get her way. See them in Gossip Girl.
Philip J. Fry accidentally cryogenically froze himself for a millennium. See them in Futurama.
If the awesome Andie Walsh is from the wrong side of the tracks, we don't want to be right. See them in Pretty in Pink.