This dress fits exactly as pictured; it is a trapeze, a-line shape. If you don’t want this shape, then buy one of the MANY, MANY shirt dresses that are a straight cut and meant for standard-sized, apple shaped women available online.
Personally, as a pear-shaped, plus sized woman, this was an amazing find. This is one of the only shirt dresses that I have found on many sites that is of good quality (not sheer, properly sewn, decent fabric) and that actually fits a pear-shaped, plus-sized woman. I would suggest sizing to your chest and avoiding this cut if you are very large busted and have a smaller bottom half- this is not the cut for you. The XXL is true to size and will easily fit a size 1x with a size B-C cup chest and a curvy bottom half.