Natsume, a sober female college student who is not familiar with sexual knowledge, encounters a filthy ● on the train one day. "Disgusting" "I don't accept physiologically" ● A man is groped with his body as he likes and is developed more and more ... - The devil's hand of a ● who endures pleasure on a train that can not make a voice, increases one after another ... Before you know it, you will be surrounded by a group and your pleasure will fall and silent filthy ● will be done ...