The embroidery on this is the reason you keep looking at it. It covers the lower half of the top in intricate contrast work - white against black, scalloped at the edge - placed precisely where the eye goes first.
The construction underneath it is equally considered. The smocked back means it fits without needing to be sized exactly. The side zipper keeps the front uninterrupted from the neckline to hem. It's the piece that makes the co-ord set worth it - and the one people come back to first when they're building the look separately.