Reiko used to work as a model, then worked for a publishing company, and lived with her husband, both of whom worked. However, her father-in-law, who she lives with, began to suffer from dementia, so she quit her job and started looking after him. Her father-in-law then praised her for her voluptuous figure, even though she had retired! Feeling pleased, Reiko showed off a provocative swimsuit, which intensely stimulated her father-in-law's penis! As if he had seen through her pent-up desires, her father-in-law's intense attack made Reiko's crotch wet, and she even allowed him to penetrate her... And without her busy husband's knowledge, their affair escalated...