There are countless ways in which a body can be posed and all aspects of it can contribute to the overall look and feel of an image.
The position of the torso to the camera can make the difference between an aggressive and strong stance or a more passive and friendly demeanor, as can the gestures of the arms and hands.
The eyes and expression of the face also have a very big influence on the way the image is perceived. A very small adjustment in the direction of the eyes and/or angle of the chin can alter the interpretation from seductive to submissive very easily for example.
Of course, knowing all this is all well and good but trying to get the desired message to come out through the images I find much more difficult in practice.