This position restricts some actions but still leaves the scope of some raunchy rubbing of organs. He clenches her posterior and PC muscles to stimulate her wildly.
Steps to perform:
Step 1: He sits on the surface folding his legs and facing his knees forwards.
Step 2: She adjusts herself to get into the position and rests her palms on the surface.
Step 3: He starts the action clenching her butts and PC muscles.