Due to a sudden car breakdown, Yuri Shinoda finds herself riding the train for the first time, only to become an unexpected victim of groping. The situation unfolds beyond her imagination, tightening her chest with confusion and anxiety. Powerless to resist, she is left entirely at the mercy of the molesters, her body teased and touched. This experience, where fear and excitement intertwine, leaves a deep imprint on her mind. Even after returning home, she can't forget the sensation, driving her to seek new thrills by boarding the train once again. What began as a random incident gradually brings a profound change to her everyday life.