Aries Shion, was the late Pope of the Sanctuary of Athena. He was, along with Libra Dohko, one of the survivors of the war against Hades XVIII century (in this century, he met Suikyo and Dohko and was the best friend of them).
Story as a villain
After being killed by Saga, just starting to Hell, leading to the grave, a secret that only he, being pope knew: the existence of Athena's cloth, which remains in his temple in the form of a statue and need your blood to back to life, it is essential to their goddess to survive in the fight against Meiou Hades.
However, Hades himself, wanting to spare his subordinate officers, it forms an alliance with Shion, pretending to accept: he would have to kill Athena in exchange for eternal life, and would have 12 hours to do this until your body turn to dust.
Shion thinks this a perfect opportunity to reach Athena and talk about your equipment, and leads a squad formed by Camus, Saga, Shura, Afrodhite and Deathmask, reborn in the nearby cemetery of the Sanctuary and begins the invasion.
Dohko will fight his old friend, and the two end up disappearing due to energy equal on both brought into conflict. Shion returns and warns the bronze saints, the blood of Athena could be used in that function. It evaporates soon after.
Shion later, the fifth film in the series, is trapped by the Olympian gods.