Ai, the daughter-in-law, is asked by her mother-in-law to see her grandchild's face. One day, her mother-in-law suggested going on a hot spring trip. It was Ai who was enthusiastic about her, but her mother-in-law ordered her to make a child at a hot spring, and she was even made to drink herbal tea that her sexual desire springs up. On the day of her trip, Ai was so excited that she could not be satisfied with SEX with her husband due to the effect of herbal tea. On the other hand, her father-in-law is also energetic and tries to hold her mother-in-law, but she refuses. In the midst of each other's agony, her father-in-law accidentally saw her naked indigo and couldn't stand it.