The moans of his mother, Reiko, leaking from her parents' bedroom. The sound was so erotic that Koichi was flustered. His friends had said they were grossed out when they caught a glimpse of their parents having sex. But within him, an uncontrollable intense emotion was rising… That emotion was jealousy towards his father who made his mother moan like that. A desire to possess his mother's love exclusively. And the forbidden desire to fill his mother's vagina, which had been filled with his father's sperm, with his own.
