Nathan Sharpe — Mr Sharpe, or "sir" to his pupils — is a tall, handsome teacher. He has black hair and dark eyes, and he often wears a smart brown waistcoat, a tie and a white shirt. He is very intelligent, an amazing teacher — but also rather strict with his students. He doesn't let them get away with anything and has no leniency for troublemakers. He especially dislikes those who are late, skip lessons or disrupt the class.