You don't see illustrated endpapers much these days, probably due to budget constraints. But I think it adds some fun and whimsy plus has an old fashioned storybook feeling to it. I'm not one hundred percent finished with the artwork yet but thought I'd take a break and give you a sneak peek.
Definition of endpapers: The plain white, decorated, or printed paper that is at the front and end of a book, one half of which is pasted down to the binding. The endpapers are used to give a finished look to the binding.