So I don't know what to do about RosenWeaon/ Tsuda Nanafushi. Basically, what he does is posts stuff here on 2chan
http://img.2chan.net/b/futaba.php?mode=cat . If that art is one of his rosen maiden characters it gets reposted to this website
http://doll-house.kazumi386.org/top.html . But you might be able to see that it's down. It's been down for a few weeks and I don't know if it's coming back.
That board has an archive here
http://www.nijibox5.com/futabafiles/tubu/index.html?view=thumb which can help up until a certain point. Usually he'll also post the same ones on twitter, but I'm kind of suspicious that they aren't the full quality ones even with the :orig on it.
