Books Beads and Baubles

A Coffee Break Mystery - Short, sweet and clean.
Bertie and her twin Wanda, own a combination thrift and used bookstore. As a service and convenience to their customers, Bertie set up a 'read-n-return' section in the book area. Customers can check out books for free, and return the books when they've finished reading them. Books begin to disappear, but no one is checking them out at the register as they are supposed to.
What's happening to the books? As Wanda noted, 'they aren't leaving the store under their own steam, that's for sure!'
The sisters live in a small town; their customers are good people who help each other, they care for their neighbors and they'd never do harm on purpose. Can the two elderly sisters solve the mystery…?