Can Belly Flashing Be A Tic?

Ok, a question for the female readers of this blog from an admittedly clueless guy: Are you aware of what your body is doing all the time? Or can you present your body in a certain way inadvertently? I ask, because I am not quite sure how to interpret certain office phenomena. Are certain actions conscious or unconscious? A couple of scenarios have popped up in recent months.

1. I have this female colleague I work with. She has this tendency to lean forward and kind of squeeze her shoulders together when we are sitting across from each other talking about work stuff. Sometimes, she is wearing a lowish top. The effect is a large amount of breast shown and accentuated. My neck usually hurts after these experiences? Why? Because I am trying to be polite, so I spend my time staring at the ceiling (while stroking my chin contemplatively and saying "interesting" a lot). Is this an unconscious habit? Or is she aware of what she is, uh, presenting?

2. Then, there is the belly flasher. There is one woman who comes by my office to talk about work or life (strange because I am not exactly what you'd call the chatty type). I guess there is some sort of magnetic field in my office that causes her to tighten up. Because she is always stretching. And she wears shirts that are short enough that she ends up flashing belly when she does that. Is that conscious? Or is it some kind of nervous tick?

Common denominator: both are married.

These are kind of subtle moves that, to me, could be interpreted multiple ways -- not necessarily as flirtation. Is it possible that they are just clueless about the potential impact of these actions? I mean, sometimes I'll be sitting down and suddenly realize I am putting on an inadvertent display based on the way I am sitting and what I am wearing. Maybe it is just a comfort level; they see me as a brother (whom they show their breasts and belly too?) or friend and just stop paying attention to those things.

I guess it would be more helpful if I gave context (any other flirtation, vibes, whether any woman in their right mind would be attracted to Joseph K, etc.). But, I just want to get reactions to this behavior in the abstract. Can these moves be anything but calculated?