A couple pages into this doc are the character sheets. Each class (or rather, playbook) has all its rules on the sheet, right there. That's not the setting changing part, it's just neat. https://buriedwithoutceremonyblog.files.wordpress.com/2017/01/reference-sheets-and-core-skins.pdf
First there's the Origins. Each one says something about how you came to be, and so that implies things about how all monsters like you come to be.
There are also certain moves, like the Infernal's _Soul Debt_ or the Queen's _The Clique,_ which define NPCs.