I've always found that the best way to pose a figure is ctually to strike a pose yourself in front of a full length mirror... Take a look at how the various parts of your body move to achieve that pose, and how those relate to their Poser counterparts. As per the indentation, it is not a girl/guy thing, though is usually more commonly identified in Men, since today's all-too-common stick-figure-women wouldn't really have the muscle tone to show that. It shows up best in people who are Thin to Medium build with light to average muscle tone, I think...