Oh, my... this is so cute (and tiny)! A new size faux book to put together with a wrap-around cover and a box area inside for hiding a trinket building a little shrine.
The finished size is 3/4" wide x 1" tall (the inside box is 14mm wide x 20mm tall x 7mm deep).
Just finish with a strip (or 2) of washi (or linen) tape on the spine. And leave yourself room for the cover to close.
Teri Calia made The Memory Keeper's Room (see the wide photo below). More info in the blog and/or see the supply list.