In the legendary repeating grade class where middle school students older than teachers run rampant, repeating their grades one after another. A school dealing with these students requested Yumi, a female teacher, to 'somehow save this class.' Gently teaching, sometimes scolding, and healing their stiff heads and crotches with a pussy vibrator - sex education. While struggling with these unconventional students, Yumi's passionate education gradually unlocks their hearts. However, the vice-principal, Yano, doesn't seem to like this style that deviates from traditional education...
