Despite all his hard work, Majime (the son) struggles with forbidden desires for his mother, Misako — a devoted teacher and wife with a voluptuous body. One night, he finds her asleep at the table after exhausting work. As he touches and kneads her massive, sagging breasts, his lust takes over. The secret revealed by Aunt Reika shatters his illusions about love and family, exposing deeper emotional and physical “chains” binding his mother. This leads to intense, taboo mother-son encounters filled with anguish, pleasure, and awakening desires