We have a feature in the pipeline called book locking... Which means that once you're done publishing your book on dbooks you can lock your book from public viewing. Then people would have to pay a rental fee set by the writer to access said content.

Of course the content would still be available for free on steemit but would lack the organization and ease of read we offer

We would really love to have you on our discord group, so we can discuss new features at length