I don't know what you were aiming for here. The work "Hourglass" is perfectly dreadful, I'm sorry to say. Very ghastly in my opinion, despite other opinions that it is creative.
If this is just preliminary work to that other end, not much to say. If this was a portrait effort to begin with, there are many problems. It is set up to look like a formal studio portrait. But it lacks all the refinement needed of such a work. The light is uncontrolled and does not accomodate both faces. It is almost a butterfly lighting on the younger woman and transitions into a poor Rembrandt effect on the older sister and is very unflattering to her nose and her left side.
I agree that the floating head effect is disturbing. There needs to either be some slight separation of her body from the background, or more of her neck showing. The younger woman's neck is showing, but the neckline is careless. The shot at first implies symmetry of their poses, but the difference is jarring.
In this type of shot, greater attention needs to be paid to complexion. Each woman has a different skin type, and the light is quite unflattering to the younger's ruddy coloring without some makeup.
This is sort of a tuxedo with tennis shoes situation. It doesn't work as a formal portrait and certainly can't be called a candid. If it went one way in either direction, it would be better.
Wow, striking eyes these two have. I'm not a portrait photographer or anything, but I'm not sure if I like the floating heads going on...disturbs me a bit.
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