In this story/world, each person has their own "inner-self," which takes on the form of an animal and physically manifests as daemons. Although it will be set during in the Joseon dynasty, this story will not be based on actual events.

Regardless of their appearance, daemons possess human intelligence, are capable of speaking in human languages, and frequently act independently of their human masters. Children's demons in their preteen years have the ability to transform into any animal, real or fantastical, instantly and willingly.

This story is not related to the Northern Lights or His Dark Materials. Just their daemons :)