I recall the robo-crow Aya from an earlier strip, but not the robo-doll Aya. Just another kappa invention, I suppose.
Biggest laughs I got were from Raiko, Yuyuko, and Futo, in that order. I'm not sure what that frame-and-box-like thing near Raiko and Kyouko is, though. Nor can I quite figure out the rationale behind Unzan's look. Also, Mystia's hat is on the road to a "yo, dawg" or Inception joke. (So is Eiki as a Rod of Remorse somehow holding another Rod of Remorse, come to think of it.)
Finally, poor Daiyousei (a "big fairy" here, indeed) looks like she needs a vacation from this image.
Perkeleee! I vaguely thought it might be, but dismissed it since the other depictions are so minimal.
I dont recognize the ones on top of meiling, koakuma, reimu and marisa
I'd guessed from the blue hood that the ghost-blob wearing it is Ichirin (as ColBoh pointed out), which would make the pink person next to it Unzan. As I noted previously, I'm not sure if can figure out why he's depicted like that.
Perkeleee! I vaguely thought it might be, but dismissed it since the other depictions are so minimal.
I'd guessed from the blue hood that the ghost-blob wearing it is Ichirin (as ColBoh pointed out), which would make the pink person next to it Unzan. As I noted previously, I'm not sure if can figure out why he's depicted like that.
It's probably because Unzan is basically a purple cloud with a face. The next logical step would probably turning him into a bishounen.