Tsubasa lives with her husband's father, her father-in-law. They were considerate of each other and lived harmoniously. One night, Tsubasa was engaged in marital relations. However, her husband had always been weak in that area, and this time too, he finished before Tsubasa could be satisfied and fell asleep. Tsubasa reluctantly comforted herself quietly. In the middle of the night, as Tsubasa slept, she felt an odd sensation in her lower body. She kicked off the covers to find her father-in-law fondling her lower half. Startled, she tried to scream but was muffled, and he said, "You're not satisfied with my son, are you?" and made her climax with his fingers. Then, with thrusts far more intense than her husband's, Tsubasa climaxed again. From then on, her father-in-law would seize any opportunity to caress Tsubasa, guiding her to orgasm. With experiences she had never had before with her father-in-law, Tsubasa became a slave to sex and eventually found herself walking towards his bedroom of her own accord...
