"Practical sex education," which was introduced as a measure to combat the declining birthrate, is sex education in which teachers "directly" teach using their own bodies. A married female teacher with a husband and two children is conflicted with embarrassment and guilt towards her family, but decides to teach for the sake of her students. There are also cases of male teachers giving direct sex instruction to female students, and a male student's sexual desire running wild as he develops feelings for a female teacher who has returned to work after giving birth...!?