This is one of the greatest graphic novels I have ever read. It deals with issues that most superhero tracts fail to do. How does a superhero deal with his powers when he discovers them as a boy? How does he live his life in a normal way?
It's really a book about life and the way we choose to live it. The emotion and feeling comes from the main character's constant meditation on life and the choices he makes. The great triumph is his growing old and having to deal with being an aged superhero. If this doesn't lend credence to the idea that graphic novels are literature, I don't know what will.