Well, I have to say this manga is amazing. There aren't that many manga out there that can surprise you the way this one does. I have been reading manga for a long time, and generally after reading a series for a while I start to expect what's coming, and although the ending was somewhat what I was expecting early into the series, the trip there wild with surprises that made me go OMFG on numerous occasions.
Some people seem to be put back by the twist this manga took towards the end but this is a Seinen and the signs were there, it didn't just turn 180 all of a sudden like some manga tend to do very annoyingly (Kurohime and Legend of Maian anyone?), in fact I personally tremendously enjoyed these twists and was very happy of the way the mangaka put them in. He put in subtle signs here and there that something wasn't right, enough to give a sort of feeling that something will happen, but not so much as to disclose what that is until it actually happens. And yes, the stuff that happens there is ridiculous but this manga gets us used to the surprisingly good combination of "yeah, I could see that happening" and "no way in hell that could happen" so it doesn't really affect the flow of the story in a bad way, in fact, I think that strange YinYang combination is a big part of this manga's charm.
I am fairly satisfied with the ending, I dare say that it tied up most loose ends although in my opinion, if the author isn't planning for a sequel, the last chapter should've either had a few more pages continuing from the last page(you'll get it once you get there) or a few less pages. He sorta just threw in an extra loose end right on the last pages after finally managing to more or less take care of all the others.
Well, sorry for babbling on, this is the first time I actually bothered to rate and comment a manga (mostly because usually there are already comments out there that say what I wanted to say) so sorry if it is a bit difficult to understand. I tried to describe the manga as much as possible without giving any details that would spoil it for the reader.
Bottom line, this manga is really one of those manga that you just must read to understand what the hell the comments are on about and make an opinion of your own. I personally loved it, and would recommend it to anyone who likes their manga to actually have a story because the story in this one is great with amazing character development.