"Another day off..." Asuka, a female teacher, sighed as she gazed upon the empty seat of a student named Yamanaka Takeshi. When Takeshi had stopped coming to school, Asuka had visited his house once, but while his parents were away, she made a mistake with him... After that, Takeshi started coming to school, but Asuka treated him coldly, and he refused to come again. But then one of the students discovered the forbidden secret between teacher and student, and Asuka...