i be not a big anime fan . i watch a lot and but none of them make me impressed like this . i be really congratulate the writer . i watch all episode ( include special ova episode ) in 1 day without move . in next 3 day and i watch two time again . it have a sci fi base gorgeous story while if you love think on complex story and this anime be a must for you . it just 13 episode and but make watcher even cry with dramatic scene . you can taste all the feeling in this series . you can see all the emotion . i have never see an entertainment that describe character psychology as well a this . so my comment be just watch if you do not yet . the best anime 4ever . 10 point be not really enough for this title and but sorry it max allow here .