In this adult role-play, track-club member Miyu is told her place in an upcoming competition is uncertain, so she signs up for an intensive three-day training camp. She arrives to find herself alone with the coach, who gropes her while she struggles through a wall sit. Claiming it will help her hold position, he presses the head of his cock against her entrance. She fights to keep her hips raised, but as her strength gives out, he gradually slides one, then two centimeters inside, beginning the ordeal that draws her into piston-like cowgirl riding and ten releases over two nights and three days.