From the end of the Curse Killing Chapter arc,
I know absolutely nothing about this series except from what I watched just from yesterday and today (1 - 20), so I just want to give my observations and perspective without reading any official information beforehand. It seems to me that the first arc was like a filler/introductory arc. The following arc "actually starts" the series. At the end of the 2nd arc, there's a horrible conclusion (fate-wise, not quality-wise). Then the 3rd one seems like a totally different scenario, but actually connects to the 5th arc in many ways -- the current arc being a different perspective of the 2nd arc.
I can only wonder what the next arc is going to be like. I predict that it's going to focus on Rena, and be pretty much in a completely different scenario than any of the arcs thus far. Most everything's been explained by now, except the mysteries of Rena.
Also, anyone know of any blooper-type material that's going to be released? This series simply reeks of quality blooper material, especially during the first few arcs where one can quite possibly get really confused why people keep disappearing and reappearing. That combined with and because characters' personalities change at so many points.