Dark Moon Manga Cover

An entry for a contest on Gaia Online Community. I've been with them for like six or seven years maybe. The online friends I made there really kept me going.
Anyways, I follow along the manga story line they have and they opened up a contest to the users for a Manga Cover for the next chapter. The characters are Gino Gambino, left, and Nyx possessing Don Kuro's body, right.
Honestly I wanted to do it all in color but when I did the moon in gray scale, well I changed my mind. I am SO happy with this I don't know what to do with myself! I just hope it's good enough to be noticed... 
Um, I did it all digitally in maybe what.... er, 8 hours? I spent four hours on it one day just doing the characters and then another four for the background (? maybe?). But I do so adore all that I did.

Please, if you'd comment on it I'd love you POSITIVE AND NEGATIVE criticisms. However, please if you have negatives to say, offer a suggestion to fix it. Though I understand if you just don't like something but why is good to know so I don't drive myself crazy thinking.

All characters to gaiaonline.com
Art is all mine~