This manga is a beautiful story about friendship and even a bit of happiness during difficult circumstances. Yes, there are gloomy situations and feelings in this one too, like being abandoned, a dear person dying etc, but the main characters handle it surprisingly well, maybe because they are just children.
The art work is great in the way it delivers the feelings and the atmosphere. The only thing I could complain about is that Rio and her brother Yuuta is a bit too similar, so you have to watch the hair cut really carefully in some circumstances to know who is who.
Overall, I do place this
among the best mangas I have read. I would give it a full 10 if it was not for some minor details, like the strange relation Natsuru got to his mother and also how both Natsuru and Rio acts like both would be older than 11.