I've had my eye on Ruthless for some time, and I actually ended up enjoying it more than I expected to. It has: 
 - An intelligent, wonderful heroine. Ruth definitely has her faults; she can be selfish, mean and inconsiderate. But she's also smart and willing to learn from her mistakes. She has an unquenchable desire to win and fight and it carried over into her awful situation. She makes reasonable decisions. This wasn't the type of story where I was constantly yelling at the MC because they're doing stupid things that don't make any sense. (view spoiler)[Though I think if I was her I would have made more of an effort to hang around the Logans' house, whether they liked it or not. (hide spoiler)] 
 - It's told in first person, but there are many third person flashbacks throughout the story. I'm not usually a big fan of this format, but it really worked for this book. 
 - Adams did a good job giving the killer a background story and "motives" for doing what he did. (view spoiler)[He just kept coming for Ruth over and over, I felt exhausted for her (hide spoiler)] 
 - I loved the writing, it felt very urgent and intense. Ruthless is also really short, around 250 pages, so it's a quick read. 
 Overall, very enjoyable. 
 4 stars