Back in Ente Isla, the other high priests find out about Olba's betrayal. Meanwhile, Lucifer's moved into the Devil's Castle and gotten Maou and Ashiya into school ghost stories.
|The Devil Climbs the Stairway to School|
Maō, Gakkō no Kaidan o Noboru
Ashiya interrupts Sadao from making a demonic speech during their offal. In Ente Isla, a woman reports on Emilia and Satan's status in Earth as well as the priest who has defected. Ashiya and Sadao arrive home to give Lucifer a pork bowl. Ashiya has Lucifer use the PC to gather information. Lucifer hacks into Emi's computer to demonstrate his ability. After Sadao chats with Emi, Emi visits Sadao at MgRonalds. Emi explains that she can use her powers to go back home, but she has to stay here to watch Sadao. When Sadao arrives home, he finds Lucifer and Ashiya suffering from looking at the land lady's bikini photo from Hawaii. Afterwards, Lucifer reveals some news about a haunted classroom at a school. He states that it might be the work of a demon.
When Sadao and Ashiya arrives to Chiho's school, Chiho's friend freaks out at her imagination of Sadao and Ashiya doing "things." Later, Sadao asks Chiho to help him find the forbidden classroom. That night, Chiho guides Ashiya and Sadao, and she explains about the urban myth and the other sixth mysteries. She states that the seventh mystery is currently unknown. Lucifer calls Sadao and informs him that a gate might be in the forbidden classroom. He explains that the gate can suck in human spirits and replenish their demonic magic. Then, Emi arrives, and when Emi puts on her slippers, Sadao has his group run away from her. Though, Emi catches to them. Meanwhile, the same woman from Ente Isla observes Sadao's group from a window on a nearby building.
Sadao's group find the forbidden classroom and signs of food and handheld console. Lucifer calls and asks if there is a handheld console. Sadao realizes this room is where Lucifer and Olba had arrived in. Chiho notices an Udon bag as the gang exit the classroom. At McRonalds, Sadao finds a letter, and when the photo comes out, Sadao faints. Arriving home, Sadao notices a woman in a kimono. He catches the young lady after she trips down the stairs.