Kana Narimiya lives a daily life of being tied up and trained by her perverted grandfather. Initially resistant, she gradually succumbs as the ropes dig into her body and pleasure builds within her. Drawn to these sensations, her desire for his cock begins to awaken, driving their relationship deeper into depravity. Soon, her grandfather's friends join in, escalating the training further, as she experiences climax after climax in an unending cycle of submission.