A black V back sits between two decorated shoulder lines in this photograph. The open middle extends far downwards. Below it, the long dark skirt widens and spreads over several steps. Small pale points appear across the broad lower area. The front is absent, so its shape cannot be supplied from this rear view or assumed to match another photograph.
If you like the rear line, compare your planned hairstyle on the actual dress. Loose hair can conceal parts of the edges, while a raised arrangement reveals more. Both are possible. Add an intended wrap or jacket afterwards and assess the outfit before and after removing it. You then choose visible back area across several real situations rather than for one pose alone.
Also inspect the skirt without its arranged photographic spread. Its position on the steps says little about moving between chairs. Request matching front and back views and try ordinary movements. Decorated shoulder lines cannot establish a supporting function. Clarify that on the real construction while using this picture as a reference for the visible V arrangement.