GVH-815 Mother-son play Yuri Oshikawa

A son wants to make a realistic figurine, and he needs detailed data on a woman's body. That's when his eyes are drawn to his mother, Yuri's, voluptuous body. "Mom, will you be my model?" Yuri agrees, thinking it would be helpful to her son, and poses completely naked, though she's embarrassed. But the son's curiosity knows no bounds, and he violates Yuri's body to capture her various expressions! And gradually...