A Gold Saint of the Sanctuary who wears the Gemini Cloth. He is the twin brother of Kanon.
The purpose of Gemini is to always exist in two parts. Good and evil. The man who wears the Gemini Cloth will either aspire to fully protect Athena or utterly destroy her. When his twin brother was exiled from the Sanctuary Saga lost control of his darker side and thus began his quest for power.
The normal duty of a Gold Saint is to guard his temple from invasion unless ordered otherwise by the Holy Father. The 3rd temple is Gemini and the one who wears the Cloth can manipulate the structure of the temple into that of a labyrinth..
Saga's dark impulses made him kill the previous Holy Father to attain absolute power. He donned a mask and went by the name of Ares to become the new Holy Father. In the final part of his scheme he attempted to assassinate the newly reincarnated Athena only to be thwarted by the Gold Saint Sagittarius Aiolos. Saga ordered all Saints to hunt down and kill Aiolos. Saga now had full control of the Sanctuary under the guise of Ares even though the baby Athena would still live on.