Huuuuh... Didn't noticed first, but in that picture, the photobooks covers are arranged to draw a pattern...
you can read "5.6"
and there are also some blue and pink glowsticks at the top of the PBs that are also arranged to draw 56.
Anyone knows if the numbers are somehow related to Makochin ????
Picture Edited so you don't think i'm a crazy old fart! 
