The Metro's anonymous corridors echo with the slapping of flesh as a mysterious figure pins a commuter against the wall, his hands greedily grabbing her ass. Her gasps fill the air as he lifts her skirt, revealing her lacy panties, and begins to tease her through the fabric. She moans, her body pressing back against his growing erection. Suddenly, he pulls her panties aside, his fingers finding her wet, inviting pussy. She trembles, her breath hitching as he expertly brings her to the edge, then pushes her over, her orgasm echoing through the empty station.