The secret love story of his brother-in-law and his lustful sister-in-law Saeko Matsushita, when his wife was busy with work and had to be away for 4 days, so she brought her sister home to cook for her husband (end). Such thoughtfulness). But who would have thought that outsiders who were worried about food and drink also worried about sex for their young and healthy brother-in-law. The two had sex continuously for 4 days until the younger sister came home without even knowing that she was was cuckolded by his own sister.