The Day We Met was a Regular Day in the Infinitely Looping Highschool, is That Normal?

The girl woke up and found herself in a high school. Although there was a brief sense of strangeness, it was quickly brought into the overwhelming daily events. The ordinary high school life, the students and teachers that should be taken for granted, the bustling school festival square... everything is going on in an orderly manner as the girl expected. But under this calm surface, some more mysterious things are slowly unfolding in unknown places...