The burgundy evening dress has a broad open shoulder line and a closer shape through the upper and middle areas. Its lower skirt widens. Long narrow pieces hang at the sides, while small pale points animate the surface. A dark bag is held in front of the waist. The image shows those side pieces in a still stance, without demonstrating how they behave while walking or at a table. Their precise attachment is also hidden.
If this detail appeals to you, ask how the pieces sit on the actual dress and whether they are permanently connected. Do not plan around removable sleeves from this picture alone. Walk with your intended bag, sit and reach forward. Watch where the extra lengths fall beside your arms and chair. The question extends beyond neckline position to how you want to handle those lengths throughout the evening. Compare a version without them if the broad shoulder line is your main attraction. That keeps the added detail a deliberate part of your selection.