Because you like Ted Wiggins in The Lorax

A crabby troll, Karkat Vantas is perpetually angry about his lot in life. See them in Homestuck.

Jack Bauer is a terrorist fighter who is scared of nothing and no one. The clock is ticking! See them in 24.

Born and raised in the darkness, Bane is determined to have the city totally under his control so that he can demolish it. See them in DC Extended Universe.

Wanderer is a Soul, a parasite sent into a host to take over their body, extracting information from them and colonizing their species. See them in The Host.

Hank McCoy is a quintessential nerdy scientist but with a few rather unconventional physical attributes. See them in X-Men Series.

GLaDOS will supply the food when you get together: a delicious cake. Of course, it could just be a trap so she can kill you. It’s hard to say. See them in Portal Series.

They say they saved Adam Jensen by turning him into a cyborg, but he's not sure saved is the right word. See them in Deus Ex Series.

Woody is a selfless leader of Andy's toys who likes change less than a snake in his boots. See them in Toy Story.

The chronically bizarre Dwight Schrute is the world’s most dependable assistant to the regional manager. See them in The Office.

A fearless superhero, Carol Danvers always aims to go higher, further, faster. See them in Marvel Cinematic Universe.

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.

Ultron is security software turned evil mastermind. See them in Marvel Cinematic Universe.