I feel the Spirit King is the same as the Pillar in Cephiro of Magic Knight Rayearth and that his will is what keeps the world together and if he leaves the world would begin to crumble. He is essentially a prisoner of his own fate.

- What if the concept behind the H-cube is similar to the "crystal thing" the Spirit King resides in. Thus it serves a similar purpose making the Spirit Kings will reality.

- Still you have to wonder who are these "people" living in Kings realm maybe only the purest of souls are allowed in, those that have lived several life times and proven themselves unwavering.