Walking to Class

Have you ever seen someone in a crowd that believes they are the only person in the world? I was walking to class and I pass this kid who is singing along to his ipod loudly and in a falsetto voice. No doubt it was some woman country singer that no one listens to in our world but in his fictitious world they do. I wonder what his other world consists of? I wonder if he ever visits our world? Does he like it? How does he allocate his time between worlds? These are questions that if I meet him again I will have to ask him. Also I would ask him if his vocal chords changed in puberty.