Tsutsujidai

Tsutsujidai (ツツジ台) is a city that forms the setting of SSSS.GRIDMAN. It is a mysterious place, secretly under the control of Akane Shinjo and Alexis・Kerib.

History
Through some unknown means, Tsutsujidai was artificially created or altered by Akane and Alexis. Anosillus the 2nd, who has been watching the unfolding of events for some time, seems to be the only one to know of the reality of the city and everyone else lives their lives as if as if everything was normal. Tsutsujidai is frequently attacked by monsters sent by Akane herself, for the purpose of deleting whoever and whatever she disliked, and the destruction would be undone by the Illusion Monsters later on, with the monster attack victims having their history rewritten to have died years before. Those same monsters also release gasses that make people fall asleep on the train, to prevent them from leaving the city, as there is actually nothing outside. The train goes in loops until greater forces demand otherwise, and the outside world is destroyed by some means when the area no longer serves its purpose. Also, memories of the appearances of the kaiju and Gridman are erased by the next day. It is unknown if anyone here is real, or if the city and its inhabitants are all part of some computer simulation.

Trivia

 * In the original draft of Denkou Choujin Gridman F, the inspiration of SSSS.GRIDMAN, Tsutsujidai was the name of the industrial high school that Ippei Baba and Yuta Hibiki attend.
 * Many of the places in Tsutsujidai are modeled after real-life locations.