User blog comment:Grievous67/One Piece to become the best selling book series of all time????/@comment-1940096-20150708180437/@comment-972068-20150708214752

I think what Terror is trying to say is that it's not a very fair or logical comparison for novels to comics. Harry Potter was sold as single novels (seven in total), while One Piece is a serialized story with multiple volumes. If you compare the sales of both, then yes, One Piece will have sold more. But that's only because One Piece is split into multiple volumes and isn't a single book. Or as I should say, it isn't a completed book.

"Harry Potter and the Philosopher's Stone" is one book. "One Piece: Volume 1" is the first volume of a book.