I knew this was going to be a dark, non con romance and I was prepared for it. Personally, I don't really care if this series started out as fan fic of Twilight. In the beginning I wrongly assumed it was a Shades of Grey formula book, that's why I expected the series to end after three instalments. When I realised the third book wouldn't give me a conclusion, I decided to wait until the last instalment would be published.
To sum up my overall opinion, I would say that I enjoyed Slave very much. I was glad to realise that the author didn't present me with a Deus ex Machina healing of Brianna and that there are still a lot struggles and problems to be solved in the books to come.
A lot of reviews mention that Brianna needs the professional intervention of a therapist, and I second that opinion. If Stephan, the new owner of Brianna, wants to develop a healthy relationship with her in a world where he isn't perceived as a God like creature by Brianna, she needs to learn to stand on her own two feet again. However, I do think that a "normal" therapist would do more harm than good, in this case a kink aware and friendly shrink would be preferable.
My one big problem with the book lies with the punishment scene. As it happens Brianna is inattentive and Stephan punishes her with a cold shower and takes away her most valuable goods, the two books he has lent her to read. In the moment of reading, I found that more cruel than I can express in words, especially since Brianna has been mistreated so abominably at her former owner's hands. It totally, completely rubbed me the wrong way and I was seriously contemplating of discontinuing the series.
However, I won't do so because I am simply too curious as how the series will turn out and overall I truly liked Stephan, so I will try to forgive him. B