Plot Summary: Devil King Sadao is only one step away from conquering the world when he is beaten by Hero Emilia and forced to drift to the other world: modern-day Tokyo. As "conquering the world" are the only skills the Devil King possesses—and are obviously unnecessary in his new situation—he must work as a freeter to pay for his living expenses!
Plot Summary: Mysterious invaders called the Septentriones arrive in Japan and begin attacking the country on a Sunday. To fight back, the heroes in Devil Survivor 2 signed a pact with the devil to become the Thirteen Devil Messengers. The Septentriones show up at least once a day and you have a time limit of seven days to defeat them.