Solid Demo, the game looks amazing in it's very distinctive style, character portraits are gorgeous too, the areas look equally spooky and mysterious and I love the idea of the never ending buildings.
The puzzles are nice, I am dumb and it took me a while but it is pretty balanced, maybe my only suggestion would be to add a little more interactions with the environment, it feels a little empty (unless that is the idea of course) the conversation between the characters feels the space very nicely and the world building so far is SuperB tho.
Can't wait too see the whole thing, keep up the good work!