Kumiko, a wife left in charge of the parents' home while they travel overseas, and her husband, Horio, visit their parents' home to find that Kumiko's older sister, Honoka, who had emigrated to Brazil after an international marriage, has returned home. While the sisters rejoice at their long-awaited reunion, Horio is captivated by Honoka's body... Honoka, who has become accustomed to life in the local area, masturbates loudly every night, not minding the sleeping Kumiko and her husband. When she spots Horio passing by by chance, she attacks him without hesitation, ignoring his pleas to stop her and forcing him to ejaculate into her vagina. After that, she attacks Horio again and again, looking for opportunities for Kumiko to have sex. She milks his sperm with her lewd body and elegant technique...