This is the sequel to "The Girl in 6E" and it is a little bit darker than the first book. This book and it's predecessor remind me of "Dexter" a lot. Highly recommend. 
 I really like the story arc in this one.(view spoiler)[ We get more of the relationship between Deanna and Jeremy and we learn more about Mike her hacker friend. This book focuses on a new threat to Deanna a rapist who was just released from Jail and comes across Deanna's website. (hide spoiler)] 
 I thoroughly enjoyed this book and the last one hundred pages I really could not put this book down I had to know what happens next. Now I am all caught up on the series and just need to wait for the release of the next book.