(I can’t believe I’m still here)
I think we’re dealing with an optical illusion, as mentioned earlier, of the oldwoman/young woman or vase/two faces variety.
You think you’re seeing a small-breasted, braless woman. You see the white triangular shape to the left of her top button as the fabric on the right underarm portion of her sleeveless top, as seen from the inside of her shirt and under the curve of her naked breast, right? And her right breast is just hanging out, inside the shirt, uncovered (except, as you say, for the front part containing the actual nipple and the right side of it).
Sorry, but no. Look at the angle of her shoulders – there’s no way that her breast could appear like that if we were seeing her naked front, without also seeing the skin of the part of her torso under the breast. Also, the color of that white triangle is all wrong to be a part of her shirt. It’s a different garment – as I said, a lightweight tank top or chemise across the front of her body and covering her breasts quite adequately.
And shouldn’t we be able to see some indication of her left breast, if her right breast is so (pardon the expression) high and jutting? But the part of the shirt fabric where it would seem to belong actually looks loose, with no skin against it. I don’t think they’s use a mastectomy patient for a model.
(OK, this picture is just starting to creep me out a little bit)