With a premise like that, it is likely already obvious that this is not exactly a happy and light-hearted story. In fact, reading this manga is almost like watching a disastrous car accident about to happen- you know it's coming, you cringe, you can't do anything about it except look on.
Most people who talk about how sad this manga is will likely relay the events that took place, the endless string of terrible things that kept happening... but for me, it was human nature itself and how desperation can spawn some of the worst choices a person can make. It's like watching something that could've been right but knowing (and seeing) that it has the very real possibility of taking a swift turn for the worst.
That said, I felt this aspect is both the strength and the weakness of this story. The author does a good job of touching you with Ayu's story, but at the same time, also did a tad bit of an unnecessary overkill in some parts. This story is something like a lesson in life- the choices you make have consequences and Ayu's life is like a string of cause and effect. To that effect, it works great... but I found that the author would throw a tragedy or two in there (to add onto an already massive pile) that kind of fell in the category of "shit happens"- which is fine, except for this type of story, it felt flat, forced, and unnecessary.
As a whole? It's a story with a great message, delivered without pulling any punches. If anything, that in itself already makes it worthwhile to read. I did, however, debate on whether to give this a rating of an 8 or a 9. A personal rating is an 8 in my book... but I think that has a lot to do with where I was/am in life when I read this, as well as, my age (over 30). To be fair, I think the story itself accomplishes and does well at what it had set out to do. For that, I give it a 9 (or an 8.5 if I could've done so)
Note: We're talking about a girl who sells her body here. Expect to see sex scenes and crude behavior.
