So, Other Tokyo is a pocket dimension, meaning that it's not possible to leave the bounds of Other Tokyo, right? You'll just hit an invisible wall? How did the 'normal human' population of Other Tokyo come into being? Are Witches able to travel between realms because they are Witches, or specifically because they possess the badge?

Also, how does magic work here? What's the difference between a Witch and a normal human anyhow? And how are contracts with Daemons formed?