Searching around the forum, I was a little surprised not to find a dedicated topic to the laws (or rules) of the invisible realms.
Most people talk with a fascinating ease about these things, like it's kind of a "no man's land" out there.

I think we should have some concerns - those areas are not...uninhabited.

Ancient scholars talked a lot about entire worlds and invisible hierachies, rankings of angels, demons, etc. - each and every one having distinct origins and duties.

What do we know about all that ?
I mean knowing, not just presuming.