Andromeda Shun is a Bronze Saint who protects the Andromeda constellation and serves the goddess Athena. He is the younger brother of Phoenix Ikki, another Bronze Saint. Shun was among the orphaned children gathered by Mitsumasa Kido to be trained as Saints. He underwent his early training on Andromeda Island, where he overcame the Sacrifice of Andromeda trial by focusing on his bond with Ikki rather than brute force, thereby earning his Andromeda Cloth. Shun possesses a gentle and pacifistic nature, preferring to resolve conflicts without violence. This reluctance often restrains him from using his full power unless absolutely necessary or when protecting others. Despite this, he is considered one of the strongest Bronze Saints, capable of formidable combat prowess when pushed to his limits. His appearance is frequently noted for its beauty.

In the Galaxian Wars tournament, Shun fought Unicorn Jabu to locate Ikki, who had become antagonistic after his training. Shun later joined the other Bronze Saints in retrieving the stolen Sagittarius Gold Cloth from Ikki. During the Sanctuary arc, he awakened his Seventh Sense and defeated Pisces Aphrodite, a Gold Saint, using his Nebula Storm technique, though he succumbed to Aphrodite’s Bloody Rose attack and required recovery afterward. In the Poseidon arc, Shun defeated the Mariner Generals Scylla Io and Siren Sorrento, sparing Sorrento by imprisoning him with Nebula Storm. The Hades arc revealed Shun as the chosen human vessel for Hades, the God of the Underworld, due to his pure soul. After being possessed, he briefly regained control and urged Ikki to destroy him, but Hades reasserted dominance. Athena’s blood later enabled Shun to expel Hades permanently. During this arc, Shun temporarily wore the Virgo Gold Cloth and ultimately achieved the Andromeda God Cloth.

In the canonical sequel Saint Seiya: Next Dimension, Shun accompanied Athena to Olympus and later traveled to the 18th century, where he allied with Pegasus Tenma and was designated as the successor to Virgo Shaka. In Saint Seiya Omega, Shun suffered a cosmic-induced dark wound in a battle against the god Mars, forcing his retirement as a Saint; he became a wandering doctor, aiding new generations of Saints. Shun’s primary weapon is the Nebula Chain, linked to the myth of Princess Andromeda. The chains offer defensive capabilities, extending vast distances and emitting warning signals or electric shocks when detecting threats. His techniques include the defensive Round Chain and the offensive Thunder Wave, which restricts opponents. When pushed, he uses Nebula Stream to paralyze foes and Nebula Storm as his ultimate, devastating attack. His relationship with Ikki remains central, often driving his actions. Over the course of the series, Shun grows from a hesitant youth into a resolute warrior who accepts the necessity of fighting to protect what he values.