Wish I could tell who that was waaaay in the back over there. Looks to me like Gilgamesh...and if you look close enough he has a nekoarc over his crotch...
Also is that Cornelius' top hat over by the watermelon? post #317467
1. Arcueid is to Ryougi's left, wearing what looks like a clam shell bikini. Red eyes, blonde hair, and the style of the hair is much the same.
2. Perhaps an assumption, but I believe the one in the sky is Fujou Kirie. Since there are a bunch of girls alongside her and they are usually "floating"...or "falling" in this case. heh heh
Setting the source to the thumbnail of the actual post, because the uploader saved only the thumbnail. See huge-o-vision parent post for actual source.