Because you like Captain Ahab in Moby Dick

Ethan Hunt's mission, should he chose to accept it, is to save the world from impossible threats. See them in Mission: Impossible.

Newt Scamander is more comfortable with animals than people, even if the animals are super-dangerous magical creatures. See them in Fantastic Beasts and Where To Find Them.

When the going gets tough, Rick Grimes gets tougher. It's a very useful trait when the world goes to hell. See them in The Walking Dead.

Nothing instills more fear in the Empire than the deep kshhh of Darth Vader breathing through his helmet. See them in Star Wars Series.

Severus Snape is a misanthropic potions teacher with a vindictive streak. See them in Harry Potter Series.

Foul mouthed and disturbingly comfortable with violence, Hit-Girl is a precocious assassin who doesn't need anyone's protection. See them in Kick-Ass.

Trying to get through school without being a burden to anyone, Tohru Honda stays cheerful despite her difficulties. See them in Fruits Basket.

Edward Elric has a quick mind along with a quick temper. See them in Fullmetal Alchemist.

An infamous vampire, Alucard is a one-man killing machine with a philosophical side. See them in Hellsing.

Spike Spiegel is a bounty-hunter with a laidback style and lightning-quick moves. See them in Cowboy Bebop.

Even the smallest person can change the course of the world, if he's brave enough. See them in The Lord of the Rings.

A bookish know-it-all with a bossy streak, Hermione Granger always stands up for what she believes in. See them in Harry Potter Series.