This manga raised many good questions such as: What is a family, what is love, what is bond, what is role, what is life. And the mangaka deliver it pretty well but the 2nd half is a little bit rush. I think it could be better if its longer but overall I like this manga a lot. But it seems like everyone have a problem with the 2nd half and the ending of the series. When I first read this manga I already know that the ending is possible. As the story goes there're many hints that show up until to the ending. If you taking into account of the characters feelings, how they act, how they think, what is their habit, what is their reaction to the question, why they refuse/accept their own feelings, why they make that decision, etc. The ending, the conclusion is, it's make sense, very logical and clear as how and why it happened. It's a very good ending.
If you like a manga that go in depth about relationship/connection/bond/interaction between people, how people think and the like, you probably like this manga and I definitely recommend this manga. But if you are the kind of people that can't deal when people with different/same gender, age, role, that kind of things getting into relationship, always expect something to go your way, mentally weak, or/and narrow-minded, then don't read this manga it's not suit you at all but if you're open-minded person then go for it.
Don't be stupid. "I'm not into guys" is a common line in BL, isn't it? "I'm not into guys. I'm in to you!" (Who happen to be a guy) - Genshiken Nidaime