This is book 6 (not counting the character books, compilation volume, or 'side stories') in a series. The individual books 1-5 and the two character books appear to be out of print, but the compilation volume containing Sachiel I&II, Shamshel and Ramiel I&II is still available from Toranoana: http://www.toranoana.jp/mailorder/article/04/0010/20/29/040010202982.html
Wish I'd snatched up the first Character book when it was released, it's the only one I'm missing.
psuedonymous said: This is book 6 (not counting the character books, compilation volume, or 'side stories') in a series. The individual books 1-5 and the two character books appear to be out of print, but the compilation volume containing Sachiel I&II, Shamshel and Ramiel I&II is still available from Toranoana: http://www.toranoana.jp/mailorder/article/04/0010/20/29/040010202982.html
Wish I'd snatched up the first Character book when it was released, it's the only one I'm missing.