I read it because I read It Ends With Us by Colleen Hoover and didn't like it. I heard that this book, although completely separate from Colleen Hoover, had a similar storyline between Lily and Atlas and could provide closure in that storyline.
I couldn't put it down because I was always wondering what Elliot had done
It wraps up rather quickly in the last 60 pages. It was satisfying enough to provide closure but I was left with a few questions.