Because you like Phoebe Halliwell in Charmed
Dolores Umbridge keeps her villainy hidden (albeit poorly) behind a sheen of sugary pink politeness. See them in Harry Potter Series.
Lloyd Dobler is a kickboxer wearing his heart on his sleeve who would do anything for the woman he loves. See them in Say Anything.
Sephiroth wants nothing more than to seize the power of the Lifestream in order to become a god. See them in Final Fantasy Series.
Darlene is a free-spirited hacktivist who follows her own moral compass. See them in Mr. Robot.
Vanellope von Schweetz is princess of the Sugar Rush game who could care less about being royal. See them in Wreck it Ralph.
Sookie Stackhouse is a waitress who can read minds and break hearts. See them in True Blood.
Frederick Frankenstein is an eccentric (O.K., maybe a little insane) professor who is excited to be delving into his family's past. See them in Young Frankenstein.
Benji Applebaum is not a total nerd. He also happens to be super into magic. See them in Pitch Perfect.
Prideful and psychotic tendencies combine to make Dr. Eggman a dangerous and villain who will squash anyone in his path. See them in Sonic the Hedgehog.