Mona is a housewife who is immersed in happiness as she breastfeeds her newborn son. However, contrary to her happy feelings, her emotions are heightened as her son sucks on her nipples, and she spends her days in agony. One day, Mona is seen breastfeeding by her neighbor Yokoyama. Yokoyama makes eye contact with Mona and tries to run away in a panic. However, Mona calls Yokoyama back, wanting to calm the heat in her body.