Caught between a rock and a hard place

The stranger behind you has lifted your hem enough so that his cock rest between your ass cheeks. Luckily, your silk panties and his slacks prevent direct contact. He is holding your hip tight, preventing you from moving. His second hand worms down between your legs, forcing your thighs slightly open.

You shudder as he begins softly rubbing your pussy through the silk fabric. It's slick and smooth and soon your pussy is wet. You know he can feel your wetness with his fingers. His cock, rock hard, is slowly grinding up and down your ass.

The man sitting across from you lifts his newspaper slightly, you see his erection. He is stoking his penis ever-so-slowly. His eyes are fixed on what the stranger is doing to you.

The stranger presses into you harder; he is forcing you closer to the masturbating man. It only takes a couple of steps; now your knees are touching the man sitting and playing with his cock. He shifts his newspaper; your lower half is shielded from the rest of the train carriage, but you are staring right at his cock.

Your panties are sopping; the stranger is fingering your pussy harder, pressing your panties deeper into your slit. The stranger's fingers catch the edge of your panties; he pulls them aside; your pussy is exposed. You gasp as he slides two fingers right into your dripping slit.

The stranger has released your hip, but pressed between his strong body and the masturbating man, you cannot move. You hear the sound of a zipper.