Because you like Rosemary Woodhouse in Rosemary's Baby
Severus Snape is a misanthropic potions teacher with a vindictive streak. See them in Harry Potter Series.
Chandler Bings keeps his friends on their toes with his cutting wit, all the while trying to discover his own place in life. Could he BE any funnier? See them in Friends.
Smart and sensitive Sam Winchester tried to escape the family business, but ghosts have a way of haunting you. See them in Supernatural.
He's an eccentric pirate making it up as he goes along. He's Jack Sparrow, savvy? See them in Pirates of the Caribbean: the Curse of the Black Pearl.
What Ron Weasley lacks in motivation and book smarts, he makes up for in loyalty and street smarts. See them in Harry Potter Series.
Belle has ready every storybook in town, and she's slowly realizing that life is no fairytale. See them in Beauty and the Beast.
After surviving consecutive fights-to-the-death (damn you, President Snow!), Katniss Everdeen is thrust to the front lines of a real war. See them in The Hunger Games .
His murderous megalomania aside, Loki is quite charming. Just don't mention his strapping older brother; he's a tad jealous. See them in Marvel Cinematic Universe.