Kanon Gemini is a major character in the anime series Saint Seiya. He is the twin brother of Saga Gemini and initially serves as an antagonist, manipulating events from behind the scenes as Sea Dragon under Poseidon’s orders. Later, Kanon seeks redemption and becomes the Gemini Gold Saint, fighting alongside the protagonists. His journey from villain to hero is marked by inner conflict, atonement, and sacrifice, making him a complex and memorable figure within the Saint Seiya universe.