His older brother and his wife went on a trip abroad, and Takashi returned home from Tokyo to stay at home. A week later, Takashi is surprised to see his older brother and his wife returning from overseas. My sister-in-law, Yuko, who was a whitening beauty, was sunburned enough to leave traces of her swimsuit. Yuko smiled at Takashi, who thought he shouldn't be looking at Yuko's sunburn marks, but asked, "Do you want to see the sunburn marks under your clothes?" Desperately trying to suppress his desires, Takashi decides to return to Tokyo, but his brother leaves on a sudden business trip, leaving him alone with his sister-in-law.