Detroit Dead City
"This is our home. We will not give it up."
The Shadow is home to spirits, but sometimes a human can blunder right on in. Left alone for long enough, they die, become spirits themselves, or become hosts to something worse. Leave enough of them alone in the spirit world long enough and they figure out how it works. Then they start having kids, too. Eventually they know enough about what they’re doing they can build whole towns in there. It’s what humans do. Build things in places they ought not to, then thrive.