There aren't many writers who can start with the concept of a literal fantasy woman, pulled from the pages of her book to fulfill her lover's dreams, and turn her from a slave into a complex hero, struggling to understand her own identity and to create herself as a real person. Jim Hines is one of them. 
 Codex Born, the sequel to Libriomancer, is narrated by fantasy book lover and magician Isaac Vaino, but in many ways the book belongs to Lena Greenwood, a dryad drawn from a pulp SF novel and Isaac's girlfriend. Libriomancer concluded with Isaac and Lena and Lena's girlfriend (Isaac's former therapist) Nidhi Shah agreeing that they'd embark on a shared relationship -- both Isaac and Nidhi would be Lena's lovers, which would allow Lena, product of her book, and thus destined to conform to her lovers' desires, a chance to become her own person by existing in the conflicting space between Isaac and Nidhi. In Codex Born, that relationship starts to play out -- both Nidhi and Isaac struggle with the dynamic, but keep on trying for Lena's sake -- and Lena continues to hope that she can find a way to preserve who she is, even if something happened to Isaac or Nidhi. 
 Read the rest of the review at Black Gate. Book provided by publisher.