Mr. Charon is a ghoul who admits spirits to the Underworld and ferries them across the River Styx—but only if they can pay or if he’s feeling generous. Aboveground, Mr. Charon takes the form of a well-dressed man; down in the Underworld, he wears dark, billowy robes. He’s a vain being and he’s recently discovered Italian suits, which means he eats through his paycheck quickly. Percy, Annabeth, and Grover convince Mr. Charon to ferry them across the River Styx because they promise to mention to Hades that Mr. Charon deserves a raise.