It is completely different from what she usually writes (a fantasy, adult, sci-fi with superheroes). You are following this woman over 300 years who lives in the 1700s  and who doesn’t want to get married to this man which lost his wife and she is being forced to do this as a replacement. She is not interested, she wants to be free, travel, and do things with her life. Then she makes a deal kind of accidentally with pretty much a devil but he obviously tricks her and he does give her immortality but she can never be remembered so as soon as she lives the room basically people forget about her and she can’t even tell hen her real name. It’s kind of a love story between her and the devil. Characters are much stronger in this book than in other ones.