I aprove of this deeply. I am a Byzantophile, I freaking love the Byzantines and I've an instant love for them, but I've seen very little Byzantium designs that catch my eyes or at least what I think he would look like, but this one took the cake. Well done, very well done.
May I ask, if you don't mind, more about the OC in general, like do you have a personality and relationships hashed out or is this more something you though would be cool to draw, cause either way it's fine.
I must say again, this is a very wonderful representation of Byzantium, possibly my favorite.