If you could spend the day with your favorite book character, who would it be and why?

Sherlock Holmes, because the way he sees things can turn the most seemingly ordinary occurrences into a great adventure.

That would be very hard to choose. But my choice is the main character from one of my favorite novels, Mathhew Swift of "A Madness of Angels", "The Midnight Mayor", and "The Neon Court".

Mathhew is an urban sorcerer; he can feel the life of the city around him, and knows the history and the legends, the myths and folklore, and I really think spending a day just following him around listening to what he'd have to say would be fantastic and enlightening.

True story, he is a character. Tony Horwitz, and Hit the Road! Or Thor Heyerdahl on a raft.

Holden Caulfield from The Catcher in the Rye, simply because I think we could have a fantastic day just talking about everyone and everything that annoys us in the world. :)

Leo Valdez from the Heroes of Olympus, because he's freaking hilarious!

Hercule Poirot. Just to watch those little grey cells at work.