First off, I loved the second season. That said, I enjoyed this OA(D?) a lot too, though I've always been a bit disgusted at the insinuation that there might/is something romantic brewing between Hei and Yin. I realize Yin is the embodiment of Rei-like doll girl that a certain type of person may salivate over and that has been used ad nauseum in anime for this very reason, but frankly I'm not one of them.
But, to each their own.
I guess my only real disappointment is that we already know how this will end, which kind of takes a lot of the suspense out of it. I'd much rather see word that a third season was in the works.
And how sad that it wasn't really April after all. Why are my favorite characters usually the ones with only partial screen time (or any)!
Oh, and Yin is a bit freaky in her jealousy/possessiveness. Who can blame Hei for having conflicting emotions towards her by season 2. :/
All in all, I'd give it an 8. It was a bit pedestrian. Certainly not better than the OVA for season one, which was just hilarious. I'm not ashamed to admit that my 8 is probably high, simply because I'd devour anything with the label DtB on it.
