Because you like Isaac Clarke in Dead Space
Helena is a mentally unstable, childish, and completely merciless. And most of all, she's an unstoppable killer. See them in Orphan Black.
As the Rose Bride, Anthy Himemiya is a spectator in the fencing matches fought over her and her power "to revolutionize the world." See them in Revolutionary Girl Utena.
A secret smoker, Margot Tenenbaum has plenty more secrets where that came from. See them in The Royal Tenenbaums.
While he might drive colleagues crazy with his antics, Jake Peralta cares about the Nine-Nine more than most things. Including personal hygiene. See them in Brooklyn Nine-Nine.
Vanellope von Schweetz is princess of the Sugar Rush game who could care less about being royal. See them in Wreck it Ralph.
Marie Antoinette may be a fun-loving queen who has it all, but her husband doesn't know how to have sex, and an angry mob wants to cut off her head. See them in Marie Antoinette.
Prim and proper Allie Hamilton was raised to follow the rules. But she's got a fiery rebellious side too. See them in The Notebook.
As Marlena Rosenbluth is finding out, confidence in the limelight doesn't always translate to power at home. See them in Water for Elephants.
Faith has a chip on her shoulder and a stake in her hand to slay vampires in her town. See them in Buffy the Vampire Slayer.
Toby Cavanaugh has trouble avoiding being manipulated. See them in Pretty Little Liars.
Anna Karenina doesn't want to be a respectable woman any more. She thinks respect was invented to cover the empty place where love should be. See them in Anna Karenina.
Eren Jaeger will erase the Titans from this world until not a single one remains. See them in Attack on Titan.