So Spaketh the Slaughterer
Watercolor is a very appropriate medium for the subject matter. I must ask if that was intentional or if you just like working with it? Regardless, I think you did well in creating this version of the cover. The overall look and feel definitely resembles a more traditional Japanese art style, which I give you kudos for, in the sense of the simplicity, medium, and technique.
I personally have a hard time relaxing and making my lines feel loose and flowing regardless of the medium I use so to see how well you work with watercolor garners my respect and admiration. I would, however, recommend darkening the shadow near her nose a little more, though this may be due to a scan or photo as the real life version of this probably bears a little more detail, so that the space there doesn't seem so empty, for even the cover shows a shadow. Or perhaps darkening where her nostrils are a little. Just an idea but I will remind that I have enjoyed looking at this painting very much, so my thanks and my respect.
