/lit/ - Literature

Trying to find a book a friend of mine told me about

I think the story began with a couple coming back from holiday to find a new corridoor in their house that wasn't there before.

Might have gotten new rooms or something as time went on, and a big gimmick of the book was the layout of the text on the page to give a visual element of, for example, the characters talking to eachother on a flight of stairs when they can't see each other.
So a largely empty page with small text representing the person further down the stairs in the dark.
Anyone know it?

>>16940326

>>16805284

>>16645445
Schopenhauer