The circle's name is A Reyvateil's Melody (ARM for short), I'll be credited as Palsa in the book, with a link to my DeviantART, Pixiv and Twitter pages.
I actually named the book, it will be called: 'Astraea: Illustrations from A Reyvateil's Melody'.
The name Astraea comes from a Greek goddess of the stars, the cover will depict two characters: Misha Arsellec Lune (in her adult form) from the Ar tonelico series, who is refereed to as a Star Singer in the game; the other will be Iris Fortner from the Atelier series, who is a reincarnation of a creation goddess; between the two, the name felt rather fitting.
First of all, sorry for the very late reply. Things have gotten extremely busy here.
Anyway, nice draft. I like how you drew the facial expression of the girl in the uncolored pic. Can I show your drawings to the others in our cosplay group? :3 Going to post them on my Facebook, then will link back to your profile here in Animesuki.
Oh, and the colored drawing is good too. Are they characters from your favorite RGP>?