Recommended? Yes. On the basis of... relationships, I suppose. And characters.
Warning: It is very bloody. And not just blood, you get to see bones and such when people get separated into halves. Or thirds. Etc.
Categories: Sci-fi ("alien/non-human humanoids, effects of a 'virus'"), romance (m/ff, kinda. Essencially, there's only one main guy, with a number of girls around him - slightly Love Hina-esque), violence (like the second season of GANTZ.. much... ripping apart. Not a lot of weapon violence).
Moral: We're all too distrusting and unkind... if we aren't so much so, we'd make better friends.
The ending was... argh. They ended with someone at the door, but they didn't show who it was.. I'm assuming it's someone that might have died. But I'm not sure. And the old grandfather clock worked.
The music used was pretty. And sad, much.
Pity only parts of the manga have been translated... I'm not sure if it'd be better than the anime though... I read the manga first, and while there was certainly more damage done to some characters... it mirrored the anime enough that I ended up watching it on 4X speed.
Erm. Yeah. It's good. But bloody. But good. 'cause it made me cry, at the end. I'm so silly.