A Difficult Two Takashi meets Taki's older brother Isamu, a realist who is attempting to prove that yōkai and ghosts do not exist. At the Taki household again, Takashi perceives a yōkai clinging to Isamu, but does not tell him directly. Takashi and Nyanko-sensei help the siblings look for what the old key Isamu returned for opens while Nyanko-sensei wards off any more scheming yōkai. Once in the "Phoenix" room, Isamu suddenly recalls why the key is so important to him, and he and the others open a locked box hidden by the bookcase, in which there are three rocks painted with flowers...