I consider this position incredibly sexy, even (or even more) if the girls is clothed, but the feet must be bare! Can't remember a thread for it. Perfect example:
From: http://hosted.justteensite.com/gallery/4/1530/ccbill/
NOTE: There is a "legs together, feet in the air" thread, but that's something different again:
http://peachyforum.com/forums/t/229659.aspx