Angel Sanctuary 2
The truth about Sara and Setsuna's relationship gets out. Not just to one or two people - the exact oppression and ridicule he'd feared surrounds Setsuna. And that's an unneeded distraction, as more of the denizens of Heaven and Hell are coming to find him.
The cast of this series gets truly large - somewhat unwieldy in my opinion, even though everyone has a part to play. This one introduces us to a blind priest, a new young angel working for Rosiel, and a third young angel. And I really like all of them, especially the priest, although I can find some pity in my heart for the one working for Rosiel. His callousness toward his followers suggests nothing good about her future.
We also get to see the first true awakening of Alexiel's power, and it's notable that it's partly manifested first from a place of gentleness. Murderous gentleness. 'Course it really busts loose when Setsuna learns the truth about someone very close to him in what's a really great scene imo.
Angel Sanctuary 3
We learned a decent amount about Setsuna's sempai Kira in the last volume, but here we get to see a lot more about his complicated relationship with his father and understand better the endless, horrible cycle that he and Setsuna are a part of. But something's changed this time around, and it's hard to tell if it's for better or worse.
Also, Setsuna's new resolve means a big change for his life - but will fate allow Alexiel, in any form, happiness? This is only the third book out of 20 so I think it's fair to guess "no."
Also, we get to catch a peek into the workings of the angels' hierarchy, and what we see is weird and unsettling. The leadership are a powerful child and a man who will not bare his face. It doesn't take long to realize something is deeply rotten in their world.
Angel Sanctuary 4
The actions at the end of the last volume have basically leveled Tokyo and killed countless people, but Setsuna is given a chance to set some of it right - if he can find it in himself to face reality. Adam Kadamon, one of the most powerful beings, stops time and Setsuna has seven days to travel into the underworld and address the heart of the issue. When he gets there, he's met by his guide to the underworld and who should it be but Kato.
Who's Kato? Well, remember how in Volume 2's review I said Alexiel's power started to manifest again out of a place of gentleness? Well, the situation was that Kato, a bully and jerk from school, had been infected by Rosiel and basically taken over. To release Kato from Rosiel's control, Kato had to be killed and cleansed so his soul could move on in some form of peace. Unfortunately, it wasn't enough to actually send him to heaven, based on his life in general. Seeing the two of them playing off one another is actually a real highlight of this series, one of the things I remember clearly from my first read-through of this series as it was being released.
Meanwhile, Katan, Rosiel's right-hand man, was all but destroyed along with Tokyo. Rosiel tries to save him by giving him one of the pills that turn people into Rosiel's puppets. He tried desperately to explain how badly he does not want that, but Rosiel's selfishness means he gets his way over Katan's objection. However, things aren't going to plan and Katan is turning into something horrible. It's weirdly sad, because I know Rosiel's a selfish, horrible person but there's something deeply pitiable about the way he just doesn't seem to understand what he's done and how badly he hurt someone who really was loyal to him.
Angel Sanctuary 5
Something has gone very wrong in the underworld. Kato has done an about-face in personality, and the two meet up with a young woman who looks remarkably like Sara but who has no care about the pain and torment she can cause. In fighting with her, the lord of the underworld himself is summoned to do battle.
Once he and Setsuna settle their differences martially, Setsuna gets to go on another redemption quest - this time into Kato's memories, to try to save his soul from being absorbed, used and lost. And while Kato's not a good person, the view into his own perception of self-worth and the world in general is very sad. But helping him is nothing next to what Setsuna's overall goal is. The thing he's looking for has been taken to heaven, and his time is almost up.
This manga is so complicated. It's one of the few I can't just breeze through. There's a lot of text, a lot packed into the lovely art, and a lot going on generally in the plot. The huge cast of characters, each with their own separate motivations and desires, also adds to it. I'm really finding that so far, this one holds up from my memory of the first read.