Zethes

Zethes is a son of Boreas and wasn't immortal. He was a demigod until his father offered him and his demigod brother Calais immortality. He travelled to retrieve The Golden Fleece with the original Jason. His sister is the goddess of snow, Khione. He doesn't get along with her like his brother Calais well.

The Lost Hero
He is said to look like a love god from the 70's. He has a bad case of acne. He is at his father's palace when Jason, Piper and Leo go there to get information from him.

The whole time Jason and Piper are in the throne room, he is hitting on Piper and is impressed when he finds out she is a daughter of Aphrodite.

He wants to turn Piper into a ice statue, because of her beauty. But he lets her go.