When Koji returned to his parents' house, he felt something was off about the awkwardness between his brother and his wife. He heard that they were trying to conceive and were having sex every night. He tried not to get too involved, but he happened to come across the scene... He was transfixed by his sister-in-law Jun, who was showing off her lewd behavior even though she noticed him. Jun desperately wanted a child, so she asked Koji for his sperm, saying that it would be a sibling. He couldn't resist her as she kept asking him to have a child while covered in sweat, and he released a large amount of semen into the depths of her vagina...