The characters within a book were, from a certain point of view, identical on some fundamental level ‒ there weren't any images of them, no physical tangibility whatsoever. They were pictures in the reader's head, constructs of imagination and ideas, given shape by the writer's work and skill and the reader's imagination. Parents, of a sort.
Small Favour: The Dresden Files, Book Ten (ed. Hachette UK, 2009) - ISBN: 9780748111787