Nothing rare about a normal Ao Usagi drawing. A lot (if not most) of his work is just regular old comedy or puns that are only incomprehensible if you don't get them. ao_usagi what returns measly two pages of results (with some blank space making the total barely over a page). AU's an awesome artist with some truly fine absurdist* works, but don't be surprised if you get downvoted when you have nothing to say but "OMG Ao Usagi my mind is broken need reboot".
Not to get all negative, this is a very nice picture. The creative wings aside, this is one of the cutest Flan pictures I've seen in a while. I also love the colours in Bunny's drawings.
The key to understand Ao Usagi is creativity (also: breasts). Most of his pictures seem to exist to showcase some original idea he had, breasts-based if possible. This is an artist that only rarely draws breastless characters just being badass or cute.
The whole dadaist/absurdist angle is misleading. The only thing that seems to matter for him is that the picture shows some kind of novelty (and/or breasts).