I have a theory; The "Dark World" and it's inhabitants don't just pop in from reality out of nowhere, it's been there the whole time, it's just that no one can see it (which is why Ralsei says "an alternate view of reality") or enter it aside from a Dark Fountain, which is basically a gateway into the Dark World, which could also explain how Darkners like Jevil have a relationship with other Darkners like TM despite one Dark Fountain being already closed and another one not being opened yet
