One day, Akemi is asked by her husband to take over the caregiving duties for her father, Norijii, as her sister-in-law is unwell. Enduring harsh scolding from her sister-in-law, who treats her like a pesky younger sister, Akemi accepts the responsibility of caring for Norijii. Feeling stressed from the unfamiliar tasks, her life takes a turn when she witnesses Norijii suddenly getting an erection during a bath. Captivated by the sight, she feels an overwhelming sense of fulfillment. In that instant, her daily stress vanishes, and a new, unexpected emotion begins to stir within her.