Sumire, the daughter-in-law pressured by her mother-in-law to have a grandchild soon. One day, the family decided to go on a hot spring trip. However, for the sake of having a child, she was ordered to abstain from sex for a month leading up to the trip. On the day of the trip, Sumire is not satisfied with mechanical sex with her indifferent husband. Meanwhile, her father-in-law tries to embrace his wife but is rejected. The two, overwhelmed by their sexual desires, head to the hot spring to calm their bodies. Then, the father-in-law accidentally catches a glimpse of Sumire bathing…
