Because you like Penny Lane in Almost Famous
Bad-ass Rayne has sworn her life to finding and destroying her vampire dad, Kagan, and killing as many other vampires as she can in the bargain. See them in BloodRayne .
Good fashion? Check. Snarky quips? Check. Supernatural evil-fighting powers? Also check. See them in Buffy the Vampire Slayer.
Number Five is a 58-year-old man trapped in his 13-year-old body. See them in The Umbrella Academy.
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.
Give in to the dark side with vampire Lestat; it's more fun. See them in Interview with the Vampire: The Vampire Chronicles.
For the sake of science, Kurisu Makise will persevere no matter how deep into the dark secrets of the world she finds herself. See them in Steins;Gate.
Stuck in space, Ryan Stone will either make it back to Earth and have one hell of a story to tell. Or she will burn into the ether. See them in Gravity.
Aldo Raine is in the killing Nazi business. And as he says, business is a-boomin'. See them in Inglourious Basterds.
Tina Cohen-Chang is a shy loner who becomes a fierce performer on stage. See them in Glee.
As the White House Press Secretary, C. J. Cregg is a master of verbal karate and the best damn basketball player in Ohio Valley history. See them in The West Wing.
Eponine is a scrappy street urchin with a bad case of unrequited love. See them in Les Miserables.
Miles Morales was bitten by a radioactive spider, put on the webbed spandex, and beat up his first bad guy before his voice changed. See them in Marvel Cinematic Universe.