The husband's younger brother, Kazuo, has been staying at the Sawamura household for several months to prepare for his exams. Feeling embarrassed about being a second-year repeat student, Kazuo is encouraged by Reiko with the promise of a reward if he does well on his practice test. Secretly harboring feelings for her, Kazuo says, 'Then, I want to kiss my sister-in-law!' As a result, he achieves excellent results and Reiko decides to give him his reward. However, she can't stop thinking about the intense, rough kiss that was unlike anything with her husband...
