Saint Seiya Hubris

Kanon, a marine biologist and activist, discovers, through his political enemy, the businesswoman Saori Kido, that he is actually Athena's Gold Saint, who fought in the Holy War against Hades and ressurected without his memories.
From what everyone knows, Athena, born in this age as Saori herself, was accused and tried for alleged war crimes against the gods and the Olympus, and as a punishment, the Gold Saints had their souls sealed. However, years later, they were released by a mysterious entity, leaving no clue.
In order to prevent his twin brother Saga from having to fight an endless war against the Olympian gods, Kanon offers to be the Gemini Gold Saint. The Gold Saints must fight one more time, because the fate of mankind cannot continue in the hands of the gods. But Kanon must find his place in this world and the identity of the beautiful mermaid who saved his life two years ago.