Kusatta Kyoushi no Houteishiki / 腐った教師の方程式

Growing up, Atsushi Arisawa was enamored by Masami Shibata, the older boy living next door. Even after Masami moved away, Atsushi has been careful to exchange letters with his childhood crush. Now ready to enter high school, Atsushi decides to attend Jougaouka High School despite its bad reputation, knowing Masami now works there as a nurse. However, when Atsushi arrives at school, the man in the nurse's office is completely unlike the kind boy he grew up with and seems to have forgotten him completely. As Atsushi tries to make sense of this bizarre reunion, he starts to appreciate the sharp-tongued nurse for who he is. ...