During class, Hina is suddenly hit by a strong urge to urinate. Unable to say that she wants to go to the toilet, she sends desperate SOS signals to the teacher, but the teacher is so focused on the lesson that he doesn't notice. (...I can't hold it in...I'm going to come!!) Finally, she wets herself right there... The boys tease Hina, who is too embarrassed to do anything. The teacher, unable to bear seeing Hina like that, quickly comes to her rescue, but... As soon as they are alone in the nurse's office, they start trying to take Hina's chastity in the name of sex education. Then, this time the boys see them...