We've been asking for parchment books for along as I can remember. Now that we have Poacher's pouchs, farmers bag, creels, using the same logic we should be able to have books.
A book as a simple holding device would be nice and ideas could be futher expanded on it,
ie
1) Clicking it to read all the parchment inside the book.
2) Being able to hold the book in hands or on pouch slot.
3) Being able to open the book while it's in your inventory or object inventory (like pelican pouch's or creels)