Because you like Minerva McGonagall in Harry Potter Series
Brilliant, violent, and only a little insane, the Joker doesn't listen to anyone except the voices in his head. See them in DC Extended Universe.
Veronica Lodge is a sophisticated girl who always, no matter what, absolutely gets what she wants. See them in Archie Comics.
Francis Freeman may be impervious to pain, but he sure knows how to inflict it. See them in Deadpool.
April Ludgate doesn't like sunshine. She's more of a blood and guts kinda girl. See them in Parks and Recreation.
Audrey Horne may seem inquisitive and charming, but she can turn on a dime. See them in Twin Peaks.
Jacob Black is the boy next door who's also the wolf next door. See them in Twilight.
Poison Ivy is a seductive, venomous botanist laments the fact that there are so many people to kill, yet so little time. See them in DC Extended Universe.
An agile and powerful swordswoman, Saber is a dignified warrior down to her bones. See them in Fate/Stay Night.
She's a survivor of gunshots, of being buried alive, nand of paralysis. And now Beatrix Kiddo is going to make her abusers pay. See them in Kill Bill vol. 1.
Rick Sanchez is a gruff, alcoholic mad scientist, with the emphasis on "mad." See them in Rick and Morty.
The cutest kitty this side of the galaxy, Nepeta Leijon is mischievous, caring, and obsessed with romance. See them in Homestuck.