Because you like Julia Sullivan in The Wedding Singer
Felicity Smoak is a brilliant hacker who nonetheless becomes tongue-tied in front of attractive men. See them in DC Extended Universe.
Jax Teller can be cool or vengeful, calm or wrathful, depending on the situation. See them in Sons of Anarchy.
Betty Cooper seems like a sweet girl, but she also has a dark side and can go beyond what's safe or sane. See them in Archie Comics.
Clementine Kruczynski thinks that too many guys think she's a concept, or she completes them, or she's gonna make them alive. See them in Eternal Sunshine of the Spotless Mind.
For Dana Scully, sometimes looking for extreme possibilities makes you blind to the probable explanation right in front of you. See them in The X-Files.
Years of constant assault by mean classmates, rude teachers, and her abusive mother is making Carrie White want to fight back. See them in Carrie.
Though seemingly caring and calm, this motel owner has a mysterious streak of intensity. See them in Psycho.
Charming and enigmatic, Amy Dunne takes her love for puzzles to a cunning new level. See them in Gone Girl.
John Locke is an eerily calm, confident believer in the magic of the island that gave him his legs back. See them in Lost.
Beware! Anton Chigurh carries a coin with him, which he forces his victims to flip to decide whether they will live or die. See them in No Country for Old Men.
A brilliant intelligence officer, Eve Polastri seems more like Bridget Jones than James Bond. See them in Killing Eve.
A born psychopath, don't expect Michael Myers to understand the difference between right and wrong. See them in Halloween.