Ruka, a female teacher who has just started teaching at a night school. During class, when she bends down to pick up an eraser dropped by a student, her gentle smile and an unexpected upskirt view make your heart race. One day, she suffers a sudden headache before class and visits the school nurse for help. Diagnosed with tension headaches caused by stiff shoulders, she agrees to receive a massage. However, the treatment unexpectedly extends beyond her shoulders—her most sensitive groin area is touched as well. Despite trying to resist, she can't suppress her feelings and gradually succumbs to pleasure.