Reno, the daughter-in-law, is under pressure from her mother-in-law to give birth to a grandchild. One day, her whole family decided to go on a hot spring trip. However, in order to have a baby, her mother-in-law orders her to abstain for a month before her trip. On the day of her trip, her husband unexpectedly refuses to have sex with her. Meanwhile, her father-in-law also tries to hold his wife, but is also refused. The two, overcome with sexual desire, headed to a hot spring to soothe their aching bodies. And her father-in-law, who happened to witness Leno taking a bath, can't control her desire...