"Dimension. World. Plane of existence." Renji offered all of those to see which Hojo would understand. "I don't know, maybe there hasn't been a situation before where this could come into play." He seemed unconcerned as he continued on with his exercise. "The world would be pretty boring if it were limited to what you believed." And Renji himself wouldn't exist, really. "It's happening, after all. Guess maybe it believes in you."