It was good... a deep, not very dark love story between a "slave" and her master. 
 It wasn't very dark really... nothing close to tears of tess. But, really, it's a diferent story (so no comparisons should be made) and for me William as a character was one of the plus of the book. 
 William was diferent... he had issues, but he wasn't messed up or cruel like most masters in slaves stories are. In the book we little by little come to understand why he keeps this 13 girls. 
 I loved that we could see william's past, his family and backround story (it was great too that the book has doube POV - we could see both number 13's and his points of view). 
 It was a light dark romance and i really liked it. :)