This interesting release also comes with a DVD. Is it a demo/movie/thing? Or is it something cool? Chances are it's just promo for the DS remake of Final Fantasy IV, but that's not going to stop being speculating.
One can only assume that Tsuki no Akari or month of light (as I like to translate it, don't take it to heart) is a vocal rendition of either an existing FFIV piece or a song written based on the themes that were so prevalent in the title. Whatever it is, I'm going to have to get hold of it to see, Nakano & Fukui arranging? Unusual to say the least.