...Otto wanted Christopher's friends to like him. He tried to approach them by the only method he knew: flirtation. This didn't usually displease them but it did make them decide that he was a quite ordinary boy of his kind, unworthy of their further curiosity. So they went back to talking English with Christopher. Otto, who didn't understand the language, was obliged to read their faces, gestures and tones of voice as an animal does - with the result that he ended by knowing a great deal more about them then they knew about him.
Christopher and His Kind (1977).