This was one of those that just came to be.  No real plan to begin with.  Then, as I worked a facial profile into the right side, I remembered a drawing exercise I used to do, "Vase/Faces," and decided to put a face on the left side, which would create a vase in the middle.  But, I wanted the left face to be different, so I made it a mysterious shadowy figure.  I have been fascinated with white lately, so, I kept the background/vase white.