From today on, "English" class is abolished, and "sex" is a required course!" The homeroom teacher suddenly announced this, and all the students were in a state of "?". However, as if to add insult to injury, a practical lesson began. First, the female homeroom teacher demonstrates. The students watch intently, swallowing their saliva, at the sight of the teacher having sex in front of their eyes! Even though this is already an amazing situation, condoms are distributed, and now they have to practice with each other! In this situation where popular girls and even virgin boys are mixed! But because it's a class, they can't refuse, so they tentatively touch each other's bodies... Even the men and women who were shy at first gradually lose their shame when they take off their clothes and become immersed in sex! This sight is no longer a class, but rather a gangbang! However, the purpose is only correct sexual knowledge and behavior. As a result, from this day on, students having sex in all sorts of places under the guise of pre-study and review are rampant throughout the school. Sex has become established as an important subject in this school.