Momoko, starting her rounds against perverts at the request of an acquaintance, boards the commuter train every morning with a strong sense of justice. However, she becomes complacent, thinking, "Surely not me, an ordinary middle-aged woman..." and is caught off guard by the pervert. Her long-neglected body recalls the pleasure of womanhood, and she forgets where she is, reacting sensitively. Instead of catching the pervert, Momoko finds herself swaying her hips for him, carrying a sense of guilt as she boards the crowded train again today...