Quite simply, the narrator and Roderick Usher were boyhood friends. This is stated outright in the second paragraph of Poe's short story. "Its proprietor, Roderick Usher, had been one of my boon companions in boyhood; but many years had elapsed since our last meeting." Poe continues to confirm this fact throughout the story by continuing to call Usher "the companion of my early boyhood." We also learn in the same paragraph that Usher feels that the narrator is still "his best and indeed his only personal friend" which in itself is strange because "although, as boys, we had been even intimate associates, yet I really knew little of my friend." The narrator reveals that it was "the apparent heart that went with [Usher's] request" that made the narrator fly to Usher's side. Truly, it is a strange situation.