This piece was meant to be unisex - sewn for a couple who would spare it.
They broke up before it was completed and I adjusted it to the female half :-(
At the beginning, the side seam was curved like at normal dresses. Then we agreed I should make it thinner. To my surprise, a plain straight line fits the best! The main shape was in the center back seam.
I used my favourite pattern for the fastener bands - I call it a shamrock :)