In this chapter, the narrator explains how he plans to trick the students into believing that the switch demon is real. First, he has to bring the demon back, then send the message to all the students, and finally, he wants to make a "fake" diary. The narrator explains that the contents of the fake diary will make the students believe that the demon has killed mumu, and that if they press the switch, the recipient will die. He also explains that they have to make the switches exactly like the ones in the real diary, so that the students will believe that they are receiving a message from the real mumu. Finally, he tells the students that they must report to him every time they take any action.