When he holds her from behind and starts gyrating her hips on his crotch, it sends greater sensations within his body.
Steps to perform:
Step 1: He sits on the surface stretching his legs forward.
Step 2: She comes top of his crotch keeping her face towards his toes.
Step 3: He now grabs her butts and adjusts her rosie on his organ.
Step 4: The wilder gyration starts now and both moan in sheer pleasure.