Because you like Carrie White in Carrie
Alex DeLarge likes his favorite milk-based, drug-laced cocktail. It helps him get in the mood for a night of "ultra violence." See them in A Clockwork Orange.
Marv is a brutish but principled thug who'd be right at home on an ancient battlefield. See them in Sin City.
Combining an innocent face with an insatiable bloodlust, Eli recruits friends to join the vampire way of life. See them in Let the Right One In.
Louis de Pointe du Lac is wanting to find a way of living that doesn't make him miserable. See them in Interview with the Vampire: The Vampire Chronicles.
This cannibalistic villain may be a loner, but Killer Croc doesn't have problems with self-confidence. See them in Suicide Squad.
Ash Williams is a houseware clerk at S-Mart and the Chosen One. See them in The Evil Dead.
If Lisbeth Salander can hurt a bastard who deserves it by digging up stuff about him, she feels good. See them in The Girl with the Dragon Tattoo.
Jack's big imagination is never limited by his incredibly cramped surroundings. See them in Room.