Tokyo is the main setting for Tokyo Afterschool Summoners and the stage for The Game. Based on the real Tokyo, it is split into 23 different wards.
Several years before the start of the story, around the end of the 20th century, the Gates opened in Tokyo connecting them to different worlds. Through the Gates came all manner of different creatures unlike the human natives of Tokyo. Declaring Tokyo a Joint Management Region the Japanese Government and the United Nations created laws to govern Tokyo and the beings from other worlds which were dubbed Transients. The Transient Act was created, which granted Transients rights that were close to the natives of Tokyo and gave them legal status as foreign exchange students.