I like the square and I like your image, but...

I would have moved the camera just a little to the left, to include just a touch of window, her foot in the lower right corner and her body a little more centered in the square. (But it is not my image, so I didn't)

Between the off-balanced composition and her pose, she looks a bit stiff and uneasy. It does put a little more edge in the image, if that was your intent.