My wife is about to give birth! My sister-in-law and I came to help with the housework.

Junta, a husband, lives with his wife who is nearing the end of her term. Since it was my first time giving birth, my wife's older sister, Akari, came to help with the housework. In contrast to his childish and selfish wife, Junta falls in love with Akari, who is gentle and full of adult charm. Meanwhile, a healthy baby is safely born, and Junta and Akari celebrate at home. Akari gets drunk and mistakes Junta for her husband...