A demiplane hidden deep inside the Ethereal Plane, created and maintained by the dreams of mortal sleepers. It is a vast eternity of constantly-changing dreamscapes. It is very difficult, but possible, to reach it by magic; however the only way Dora knows how is through obscure occult rituals rather than actual spells. It’s a place haunted by night hags who stride through the land of dreams like demigods, with connections and windows to every other plane of existence. Anything that can dream can touch it, slip in and out, and contribute to its ever-shifting madness.
First Reference: Chapter 10
Other Notable References: Chapter 22, Chapter 23