Because you like Number Six in Battlestar Galactica
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.
The only thing Albert Wesker cares about is turning himself into a God. See them in Resident Evil Series.
It's hard enough fighting a war. But it's worse for Commander Shepard, knowing no matter how hard you try, you can't save them all. See them in Mass Effect.
A devoted butler, Alfred Pennyworth is both a fiercely protective guardian and a lethal gunman. See them in Gotham.
Once a loving family man, James Heller is now dark, damaged, and hell-bent on getting revenge. See them in Prototype Series.
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.
April Kepner is an excellent surgeon, but outside of the operating room, she's more anxious than most. See them in Grey's Anatomy.
A determined and cold-hearted spy, Cassian Andor will do what it takes to stand up to the evil Galatic Empire. See them in Rogue One.
Bedside manner is for chumps, not the brilliant Dr. Gregory House. See them in House M.D..
Norma Bates may look like a harmless housewife, but don't let that fool you. See them in Bates Motel.
Artemis Fowl understands the way of the world. If he wins, he's a prodigy. If he loses, then he's crazy. That is how history is written. See them in Artemis Fowl.
Obi-Wan Kenobi is a sage Jedi who doesn't need to say much to teach you a galaxy's worth of wisdom. See them in Star Wars Series.