I unexpectedly witnessed my parents' nighttime activities. Yuusuke was shocked by the sight of his mother, Chisato, having an expression he had never seen before. He couldn't be happy about the possibility of having a younger sibling. What welled up was intense jealousy. Yuusuke, who wished that his beloved mother would only love him, was driven by the impulse to fill Chisato's vagina, which had been filled with his father's semen, with his own sperm. Yuusuke, who forcibly subdued Chisato, said, "I'll get Mom pregnant," and poured hot semen into the deepest part of Chisato.