Eriko Miura, a married woman who lives with a strong sense of justice, is suddenly and unexpectedly molested on a train. Normally alert and cautious, for some reason she finds herself emotionally stirred by the man's lewd advances, moaning aloud in the crowded car. The intense, unfamiliar pleasure burns into her mind, awakening complex emotions within her. Though outwardly repulsed by the assault, deep down she harbors a secret thrill at being touched in public. Just as she begins to process this shame, the man creeps up behind her once again—ushering in a new, bolder phase of humiliation.