Because you like Oskar Schindler in Schindler's List
Brilliant, violent, and only a little insane, the Joker doesn't listen to anyone except the voices in his head. See them in DC Extended Universe.
Armed guards, FBI agents, notorious serial killers – Hannibal Lecter has bested them all, with time to finish dessert afterwards. See them in The Silence of the Lambs.
Tracy Turnblad's got rhythm, and she's determined to share her dance moves with the world. See them in Hairspray.
Barbara Kean is loving, selfless, and caring. But, she's less stable than she'd like to admit. See them in Gotham.
Mystique is a shape-shifting mutant who, after too many disappointments, does not want to co-exist with humans. See them in X-Men Series.
Lelouch vi Britannia is a high school student by day, masked destroyer of tyrannical empires by night. See them in Code Geass.
His superiority complex coupled with his bitter desire for revenge makes Vegeta a formidable foe. See them in Dragon Ball Z.
Just because Dracula wants to suck your blood doesn't mean he's not a gentleman. See them in Dracula.
A lone wolf with a confrontational streak, Bigby wants to dedicate his life to doing good. See them in The Wolf Among Us.
Everyone is just a chess piece, and Izaya Orihara is a master player. See them in Durarara!!.
A fun-loving jokester, Alistair isn't ready for the responsibilities he faces. See them in Dragon Age Series.