The King in Black of Chaldea, Bruce Belmont, has been sent to Kivotos by Zelretch. Is the big city full of students and guns ready to receive such a Sensei? What will girls learn from an Occult Detective who often plays masked vigilante and mad scientist?

In one world, Kivotos would be visited by a single, normal man. Fate in this other world will be different. Now several servants run around the city helping the students or causing troubles for them. Chaos has come to Kivotos. So basically, just your ordinary day in the city of academies.

A year has passed since the disappearance of the GSC president, and Kivotos has fallen into disarray. During such a desperate time, a mysterious man suddenly appears before acting president Rin, claiming the role of 'Sensei'. But is this person truly the one Kivotos was expecting?