I just finished watching it...
It was good, but the whole time I was watching all I could really think about is how much I hated the main character. but I loved the ending because...
Spoilers:
all the characters get what they deserve.
Makato is killed
Since Sekai cant be happy without Makato and she would be misereable raising a baby by her self, the only possible solution is for her to die
and Kotohana wont ever be happy without having Makato only to herself, and the only way for that to happen is if he is dead (she keeps his head)
Does this sound like a happy ending? Well it is. Pretty fucked up huh?
...but other than the ending being brutaly delightfull, there was some pretty interesting stuff before that. Like "the rest area" but I wont get into that...