User blog comment:Xilinoc/Ch. 547 - Peace from Shadows/@comment-29183117-20130904140716/@comment-11051098-20130904174757

Yes, very clever move. It was unexpected, but now that I think about it, I'm not really surprised. This explains everything, like how the Stern Ritters could enter and leave the Seireitei undetected - they were there the whole time, just hiding "in the shadows". Genius.

Now I understand what the darkness above the Wandenreich HQ is - it seems it's simply "the shadows". It's just the other side of the paper, basically.