Who's-Who is a prominent antagonist in the anime and manga series One Piece. He is a former member of CP9 and currently serves as one of the Tobiroppo, the elite officers of the Beasts Pirates led by Kaido. Known for his cunning intelligence and feline Zoan-type Devil Fruit abilities, Who's-Who is a formidable fighter with a mysterious past connected to the World Government. His role in the Wano arc is to track down Yamato and eliminate threats to Kaido's rule.