The Dream include any people who live between dimensions and subsist on the essence of dreams of others.
The name of their parallel world is simply called The Home to The People of the Dream, it’s considered an off-limits world. It’s asleep, so to speak; nothing happens there.... More, and is considered an off-limits world. It’s asleep, so to speak; nothing happens there, and entering it runs the risk of being lost to time and awareness, floating forever in unconscious imaginings.
As a matter of note, the occupants are all asleep, so they don’t care what their world is called or who comes along.
Members of the Dream are relatively mysterious. Most of them live between known dimensions, traveling the roads between waking and sleeping, and very rarely come into contact with anyone in the waking world. Most of the time, people who are awake can’t recall interacting with them.
They need the dreams of living beings to survive. They’re not exactly parasites, and they’re not exactly monsters, but they are very much not human, and can be nightmarish. The Dream also have spooky control over plants, for reasons unknown. Under the control of the Dream, entire armies of trees can and have marched on their enemies like giant wooden puppets.
The Dream have one very clear wish: to be left mostly alone. When they do interact with others, it’s quietly, often with no verbal communication.