Not all women have the same body shape. Dawn is somewhere between a hourglass and triangle shape. I've absolutely seen women with similar proportions albeit normally with wider hips. Antonia is more of a ruler shape (also sometimes called "banana").

Read this:  http://www.womansmagazine.net/how-to-test-your-body-shape.html

This is handy: http://ninasquirrelly.deviantart.com/art/12-realistic-woman-body-shape-chart-301110737

Do a search on Google or Bing for "hourglass figure" or "narrow waist" and you'll find real women with hourglass shapes (not all are Photoshopped). Some are subtle; some are more extreme.

Example:

http://www.fashionz.co.nz/images/stories/Advice/styledoctor/hourglass-figure.jpg

http://www.bing.com/images/search?q=hourglass+figure&qpvt=hourglass+figure&FORM=IGRE

I actually had an acquaintance about 10 years ago who had a severe hourglass figure. The lower part of her rib cage came in so severely that it was causing her medical issues. As she had gotten older (read: late 20s), it had become more of an issue. She elected to have surgery to widen it slightly.

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