The Reality World is the foundation of all deep worlds.
In the Old Era, the Exorcist Association believed this world stood in a space filled with brilliance, where the sunlight from the sky cast shadows as hell, and the shadow cast by the oil lamp was the Ghost World.
The houses blazing with flames, crackling campfires, flickering torches, swaying candles, swirling fireflies, and streetlights casting a glow, they pulled shadows that were solid, gigantic, slender, illusory, wavering, and faint.
And these shadows formed one world after another.
They were born from the foundation, yet did not belong to the foundation.
But with the advent of the Weird Times, the veil of reality grew thin, and the frequently appearing deep worlds made the notion of a shadow reflection no longer accurate—
The current world is like an ocean, where the reality and deep worlds correspond to the sea surface and seawater.
