I'm a well read grad student who's bluntly honest about all things, although I try to be most honest about myself.
I hope this keeps up. Loke's backstory was the most fascinating in that it had the most depth, and made him confront a moral problem that had more shades of gray than any before. I wanted to know more about him, about where he came from, and about why he acted in the way he did. (I can't get less vague without spoiling this entire storyline.)
It also touched me the most. I felt more for the characters. The art, in addition, continues to get better and better in my opinion. It's not quite as noticeable between volumes: there was one large improvement, then slower improvements over that. Still, I really appreciate this fact.
Onto volume ten.