Hm. I tend to specialize in hard to get 
characters, rather than hard to get shows, 
but....

This one's rare enough that I've only ever seen 
two cels from it both on YJ, from the same 
seller, and I've yet to find a subtitled version 
of the show. These two cuties (brothers Shiva 
and Cipher) are from the shoujo show "Cipher."



And while not as rare as that, I think I've seen 
more repros from the Gravitation OVA than I have 
actual cels (I've seen ... about 9 actual cels 
total, including 1 I sold off a while back).