Because you like Granny Weatherwax in Discworld

Gruff and sarcastic, Detective Harry Dresden use unconventional ways to track down perps, including using magic and the supernatural. See them in The Dresden Files.

Sabriel is smart enough to understand the dangers that await her and brave enough to face them anyway. See them in Abhorsen Series.

There must be quite a lot of fellows who haven't got anybody to bring them tea in the morning. Bertie Wooster is lucky to have his valet, Jeeves. See them in Jeeves and Wooster.

A formerly righteous wizard, Saruman has been corrupted by the forces of evil. See them in The Lord of the Rings.

Remy Hadley is a closed book—a cynical, super-smart closed book. See them in House M.D..

Leonardo is spiritual, and devoted to more than just pizza. See them in Teenage Mutant Ninja Turtles.

Ted Logan wants to party on, but if doesn't get an A+ on his history presentation, he'll flunk out and be sent to a military school in Alaska. See them in Bill & Ted's Excellent Adventure.

Jenny Flint is a devoted wife and daring crime fighter, which is pretty unconventional for a Victorian maid. See them in Doctor Who.

This android may not have emotions, but Lt. Commander Data's curiosity about humanity is endless. See them in Star Trek: The Next Generation.

Davos Seaworth is steadfast, intelligent, and trustworthy, which are hard traits to find in a place like Westeros. See them in Game of Thrones.

Jail hasn't broken Andy Dufresne's spirit, but will his spirit help break him out of jail? See them in The Shawshank Redemption.