I replied in a different thread to this also....
Hi there,
The only cloth of Chuck Clone Cloth that will work for appearance of shirt tucked in is the Bodysuit. It's very body hugging, but with a good bump map it can be improved. The collar would have to be done with photoshop, drawing and using shadows.
The other cloths such as Casual, would only work for shirt over the pants. And of course suit, overcoat, and hoodie are not suitable. In the case of your picture, you have both tucked in and part hanging out - that would be really tricky.
For G3 I was able to achieve the look here - and as I improve with photoshop, I might be able to do a better job now than when I did that.
http://city.reallusion.com/ContentPreview.aspx?i=JIC294bc323430210462&g=
It may be possible to do this using sculpting program to alter the mesh, but I'm not sure, I would have to try. Anyway, were you looking for entire shirt to tuck in or half in half out as in your picture.
Alley