After years of her husband's absence due to a work transfer, a lonely mother gives in to temptation and seduces her own son. Her secret is threatened when her son's homeroom teacher unexpectedly arrives for a home visit. As a result, the son commands his mother to endure deep humiliation. The mother's inner loneliness and complex relationship with her son intensify the tension, leading to a dramatic progression. This story captures how the unexpected events within the household transform and deepen the bond between mother and son in a new, taboo way.