What is the importance of Tokyo in the novel, After Dark?

Tokyo is the city in which all of the action of the novel takes place, except for the alternate reality which exists in an entirely different realm. Tokyo is presented as a massive, glowing, neon city full of every sort of human imaginable. There are gangsters and criminals and violent psychopaths, but there are also kind former pro wrestlers and charming tambourine playing college kids and girls who are running away from their past and trying to figure out how to still have a life. Murakami's Tokyo is a place on the edge of the world, right up against the border that separates reality from a dream world, and the dream world is seeping slowly into the Tokyo night.