I love this manga. It's really pretty good, and I would suggest reading it. Maybe I'm a mature junkie? Who knows. But the mature-ness was just what I was looking for, and their is some depth to the manga, at least. Different from many of Shinjo Mayu's other works, and that's what I like.
The one thing that makes me waver: Kurumi. The female protagonist is so annoyingly stupid I could off myself, because it ruins the manga slightly for me. I wish she were a little stronger, smarter, something to give her that amazingness. It maybe wishful thinking, and I know she adds to the drama slightly (?) but c'mon, really. The innocence thing can only go so far in this manga, when it demands maturity like this.
Besides that, the manga is really good, so don't let Kurumi stop you. If you're into the maturity and the not-the-typical shoujo thing, I definitely recommend this. ^^
EDIT: The ending is stupid and sad, damnit. D= And, after re-reading this, I lied. Let Kurumi stop you. Really, there have been some dumb ones, but Kurumi takes the cake, and I mean that.