Their native land known only as Oblivion or The Great Abyss has three distinct layers, as I have come to learn. Each with its purpose and reason for being.

Kalopsia

The demon told to me that upon entering Oblivion, you are supposedly greeted with what has been deemed "The Shallow Layer". It is the surface and at face value layer that allows passage between Oblivion and The Garden. It spoke to me about how this layer is a sort of gate between the two worlds.

Avon

The secondary layer, subsequently deeper within Oblivion is, as described, a divine realm. It is where beings of immense power with unknown origins and so profound, that they are beyond the comprehension of even Oblivion's natives, reside.

The Great Abyss

Lastly, the final layer of Oblivion is supposedly the most unsettling. It is where all lost souls who had committed vile acts, sinners, and those who would eventually become demons wander for all of eternity in endless darkness. Heathenistic acts are common in this layer below all, shrouded in darkness and left unseen but heard. This is where Ronto resides.