Tantalus

Tantalus is a mortal who died and is being punished by never being able to eat or drink. Every time he goes near food, it moves away. He replaced Chiron as Camp Half-Blood's assistant director for a time during The Sea of Monsters when he was suspected to have poisoned Thalia's tree. He did not like students, but seemed to enjoy Clarisse and was the person who decided to send her on the quest. Tantalus returned to the Underworld after Chiron was reinstated.