Iori Nanase is a slender, busty competitive swimsuit instructor. Her voluptuous swimsuit is so attractive that the students are intrigued, but when she is submerged in water, her erotic body is emphasized even more. The wet swimsuit clings to her body, enhancing her charm and unconsciously arousing the lust of the students. Because she is a kind person who cannot refuse even when she is approached, she secretly holds sex lessons by the pool.