FNS-204 Guerrilla piston cowgirl Rui Shinomiya secretly seduces a timid man on a night bus after all the passengers have gone to sleep.

On a quiet overnight bus, with passengers asleep, a woman in a miniskirt that barely covers her panties, flashing her cleavage, begins muttering to herself in her seat. "Huh? It's gone." "I brought it with me..." The kind-hearted M-man sitting next to her asks worriedly, but for some reason, the woman snuggles up to him. She presses her soft breasts against him, and while the driver isn't looking, she grabs his penis and straddles him. She begins thrusting in time with the vibrations of the bus, and the engine...