Ferdinand is a minor posthumous character in the Percy Jackson imagination world franchise.
History
He worked at Camp Half-Blood. He participated in a quest to obtain Persephone's pearls, likely as a protector for one of the demigods on the quest. They successfully retrieved the pearls, but, on the way back, were attacked by some of the Morphers' creatures. During the resulting battle, Ferdinand was petrified and killed by a Witch. Said Witch would adopt the moniker of Auntie Dubayou, and place his petrified corpse in her garden of statues.
Percy Jackson and the Olympians: The Lightning Thief (Imagination World)
An unknown amount of time after his death, his nephew Grover Underwood would visit the garden on a quest, and discovered him. Initially amused by the statue's resemblance to his deceased uncle, he realized where he and his companions were, and ran off to warn them.
Personality
Almost nothing is known about his personality due to dying before he could appear, but his nephew remembered him fondly.
Appearance
Whereas he was not seen alive, he appeared to be an average satyr, with larger horns than his nephew would grow, and had a mole on his face that served as an identifying feature.
Trivia
He is the only known named casualty Camp Half-Blood sustained in the war between the Morphers and the camp.