J-cup office worker Ren Gojo stands out on the crowded train and lives in fear of a stalker who gropes her every morning, following her even when she changes cars and schedules. One day his touch feels disturbingly different, and unwanted pleasure gradually gives way to craving. His fingers make her lose control and piss through a huge public orgasm. After the train assault, they devour each other in passionate sex, and unable to forget the pleasure, she returns to the same car the next morning.