Fukushuu no Megami: Nemesis

A doctor leads a monotonous life at his institute until his cousin Mika, also a physician, is rushed to the emergency room after an accident at the school where she worked. His father orders him to take her place as the school's substitute doctor.

Upon arriving at the school infirmary, he discovers signs of vandalism. While inspecting the desk drawer, he finds a hidden envelope containing a photograph of an unknown girl. Intrigued, he begins to investigate who she is and what truly happened at the school.