From Trinity BAKumA:

Kurose Urumi, an antisocial woman, just became a new teacher. On the first day of her job, she arrives in an empty classroom with a single laptop. Suddenly, a girl materializes out of the laptop, claiming to be her student, and explaining her job as a teacher is to “download the other students and help them graduate!” Kurose reluctantly agrees to the task, and slowly finds out that her job may be fun after all.