My friend's wife is a lewd tutor

Yuuna is assigned to teach Shinya, the son of her husband's boss, how to study for entrance exams. However, the young Shinya soon becomes captivated by Yuuna's pheromones and is unable to concentrate on his studies. When Yuuna sees the young Shinya's erect crotch, her sexual desire, which has not been completely satisfied lately, is ignited and she masturbates in the toilet... Later, when Yuuna is accused of making it even harder to concentrate on studying because of Shinya's gasping voice, she says, ``If you will help me concentrate on studying, I will take off one layer at a time,'' and begins a special lesson in which she uses her body to increase Shinya's desire to study.