Rieko, who has worked for the Sanada family for seven years, accompanies their eldest son, Kyoosuke, to Tokyo when he moves there for university. Knowing Kyoosuke is anxious about living alone, his father asks Rieko to go with him and take care of him. On moving day, as Kyoosuke excitedly carries his belongings, he slips on the stairs and falls. Though unharmed, he develops a fear of staircases. Worried about his condition, Rieko begins subtly flashing her panties, swaying her skirt deliberately, hoping to comfort and soothe his troubled mind.