A hollowed-out book that contains something other than pages is literally a fake book. It looks like a book, but it is a fake. It is not a real book.
It's a art piece that has been changed to another type of art.
Book -> performance art
Although since inside is a written story, I'd argue it's still a a book, unless it leads to further clues then it becomes performance art.
A good example of a fake book is a book made of plastic which is then used in ikea or has a hidden void.
I guess I meant more written words, than a story.
But it does seem to follow onto some sort of 'club'
Either way, to me it's great art.