Because you like The Wicked Witch of the West in The Wizard of Oz
John Wick is a widowed former Navy Seal who becomes a notoriously effective hitman, killing over 124 people with gunshots alone. See them in John Wick.
The fearless bodyguard of Rick Flag, Katana will ruthlessly kill her enemies, trapping their souls in her sword. See them in DC Extended Universe.
Call her. Beep her. If anyone's in trouble, Kim Possible is there. See them in Kim Possible.
A scary monster on the outside, James P. Sullivan is really a softie on the inside. See them in Monsters, Inc..
The Ice King is lonely and looking for a princess to sweep him off his feet. See them in Adventure Time.
Maria Rambeau is a tough-as-nails Air Force pilot who is also a loving single mom. See them in Marvel Cinematic Universe.
Danny Zuko's car is auto-matic. Its system-matic. Its hyyyyydro-matic. Why, its greased lightning! See them in Grease.
A self-proclaimed diva, Mercedes Jones is on the hunt for a stage worthy of her talents. See them in Glee.
Angela Martin is uptight and puritanical, outside of the affair she's having with a co-worker. See them in The Office.
After years of living vicariously through other people's heroic stories, Wade Watts is about to become a hero himself. See them in Ready Player One.
Driven and straightforward with high-technology parts, EVE was sent to Earth to see if it is habitable. See them in WALL-E.