I have mentioned this one before, but the
official site has been uploading with a bunch of info, right now the site was slightly redesigned to be more graphic so there are a bunch of images of the characters everywhere, furthermore they are usually updating with events each day or close to that; for example compared to the last time I checked now there are a bunch of wallpapers, more info about the staff that works on this, information about the ending theme (song by Tamura Yukari) and other stuff that I haven't made head and tails as of now