Because I know you like ideas, I will bore you with how I got this concept. When @f3nix introduced a tessseract, I took that as a clue, or at least permission to explore the fourth dimension. I did a little research and picked up on his first paragraph where he described the wind as a

snake that crept in every small recess

Well, there I had it, a concept, sort of what it would be like to breach the fourth dimension. In this lecture the narrator describes the kind of shape we should visualize ourselves in as a "long undulating snake". We would have to reconceptualize shapes, directions, space. So that's why, when the dimension is breached it fills the room in which they live and stretches out formlessly. They are separated, because they cannot orient in this new spatial reality.

I had to tell someone because it was so much fun sorting this out.