My graphic design teacher and I hate the Twilight book covers. They are not clever at all, just a pale woman's arm with an apple. I know you're not supposed to judge a book by its cover, but still.
The book sucks too :I
But onto your drawing.
The vectors are nicely done with the shading, they just don't mix at all. And why is Applejack there? I know there's an apple, but still.