Wrote a review on this, here it is:
https://terrenceswiff.wordpress.com/2017/01/02/blue-friend-2nd-season/
I wrote a review for Blue Friend/Blue Friend 2nd Season, since 2nd Season is one of my favorite mangos. It is my opinion that the 2nd Season (volume 3) of this manga is quite a lot better than the first (volumes 1 and 2). They're completely different stories, and the 2nd Season story is pretty lighthearted and nice while also examining some interesting culture things. The first story is quite dark, however, and fairly depressing, but it's admirable how bold it is.
I go over this more in the review I wrote, so I suppose you can check that out if you're interested.