A Problem of Perspective

The original  Project of Doom quilt is very two dimensional.  If a book is leaning, it is leaning to the side and not backwards or forwards.  I want to include a couple of blocks that do have a 3-D perspective.  Here's  Zonko's bag:

 

The problem with this bag is that it is sitting on the background, not on the bookshelf.  A magical Zonko's bag COULD sit in mid-air, I suppose, but I want mine to sit on the shelf.  So I need to take out  the background under the bag and put in shelf fabric.  Depending on how that looks, I'll have  to decide if I need books sitting right up against the bag. or if I can leave the background fabric on the sides of the bag. 

 

This is getting more complicated than I thought it would be!  Keep in mind that I am not an artist, and my drawing skills are about at a third grade level.