For the very first time, Aoi experiences chikan (grope) aboard a crowded commuter train. Her perverted boss subjects her to increasingly intolerable sexual harassment, even groping her ass within the tight confines of the carriage. Finally finding the courage to speak out against his lewd actions, she shouts "This man is a groper!" – only to see him arrested and lose both his job and hers as a result. Hoping for some semblance of peace following this tumultuous event, Aoi soon discovers that her vengeful ex-superior has assembled an army of like-minded deviants intent on seeking retribution against her.
Cornered amidst the hidden nooks and crannies of the train car, Aoi is silenced by the threatening presence of their rigid members. One by one, these masked men take turns violating her in complete silence, using their hardened penises to forcefully claim what they believe is rightfully theirs. To add insult to injury, they unleash torrents of hot semen onto her defenseless body and face – reducing her once pristine appearance into a soiled mess of shame and degradation.