While traveling together for work, a torrential downpour forces him and his sister-in-law Miu to share a hotel room. Her soaked clothes turn transparent, and being alone with his brother's alluring wife sends his self-control slipping away. Knowing he must never touch her, he nevertheless attacks her while they are both still drenched. Once he gives in, he cannot stop: he cums, gets hard again, and keeps devouring her until sunrise, filling her with ten creampies during their forbidden affair.