Her son brings his friend Kosuke home after club activities. Maiko serves him her home-cooked meal, but notices him glancing at her chest... Later, she accidentally catches a glimpse of his cock, and becomes aroused by its strength, so she Kokoro takes a bite. While she has sex with her son's friend without much thought, Kosuke is drowning in a pleasure he has never experienced before, and continues to seek pleasure again and again. Before she knows it, Maiko's body can no longer withstand his intense and tough sex...