So, there's a MOONS-010 which contains 6 drama tracks. I always thought it was attached to this one (as in, both were enclosed together.) Sadly, there isn't much info outside of file-sharing sites.
EDIT:
This could be the drama disc
http://page.auctions.yahoo.co.jp/jp/auction/129167928
EDIT 2:
Changed my mind. The drama disc s a preorder bonus, so it needs a separate entry.