Yuki-chan begins taking lessons from a coach at a swimming school she knows. As she diligently practices her swimming, the coach's gaze keeps drifting toward her crotch. Unaware of his stare, Yuki continues concentrating on her training. In the water, she fails to notice the coach's hands checking her form as they support her body, completely absorbed in her strokes. Throughout the lesson, the coach repeatedly touches her in various places, yet Yuki remains oblivious, progressing through the session without realizing his actions.