Demons have begun to flow into Equestria through summoning portals created by ponies across the land at the request of a mysterious mare. These demons are then controlled by "Tamers" ponies who they decide to form contracts with and fight the battles of that pony. Princess Celstia seems awfully afraid of these new developments ordering a shield around Canterlot, ordering her royal guard to burn all of the bodies in the graveyards across Equestria and summoning demons herself to protect her and her sister. It's up to Twilight and various others to figure out what is going on and what is the Shin Megami Tensei?