They’re from show me your mui mui. My friend is wearing this exact dress in an upcoming wedding. I will warn you, it’s not terribly flattering on non-model bodies. It’s also cut in a way that makes any shapewear or bra nearly impossible.
I was going to make the same comment that it seems this type of dress is for really skinny ladies with not much of a bust. If your ladies have these body types go for it but I have an hour glass figure and border plus size so that style would not look good on me.