Thousands of years ago, the people of Rosemoor and the mortals used to live in harmony. The Rosemoors mostly out to help the mortals with their day-to-day needs.
The plants and root crops needs to be watered? Rosemoors with gifts of the water came to the rescue.
The rice field needs to be burned down for a new harvesting season? Those Rosemoors with the ability to produce and control fire came to help.
For a long time, the two different races coexisted without trouble until the humans pursued industrialization and modernity.
Foreseeing the danger of continuing to live together in one world, the Rosemoors took a step back and concealed their world to the mortals.
All the older generations who lived to see how bountiful and abundant the world was when the spirit creatures and mortals coexisted eventually died and only a few of the few mortals today know about Rosemoor's existence.