Assuming that the torso length isn't too long, I'll make a comment that seems to stir up a lot of negative comments from those that like to "make a frame" with their foam pads. I've personally never understood why you would want to make a frameless pack rigid with a foam pad as it defeats the benefits of using a frameless pack.
In your picture, the pack looks like a stiff board which suggests that it has been stiffened with a pad or frame sheet of some sort. This will often cause the pack to tip away from the shoulders and the user will cinch up the shoulder straps to try and bring the pack back closer to the shoulders (and cause shoulder pain from tight straps).
Try removing the frame sheet or foam pad and just fill the pack with your gear and then "shape" the pack to fit the curve of your girl friends back. I can make my frameless pack follow the contour of my back perfectly by bending it with my hands (or my knee if it's a tightly packed load). The key here is to pack the frameless pack with a fairly rigid load (but not rock hard) and shape the pack as needed for best fit.
Some people seem to like the "stiff board" effect that a foam pad creates when added as a frame, but I've never liked it. Give it a try without a foam frame sheet and shape the loaded pack to fit and see if it makes any difference.