He is one of the 88 saints of Athena, and one of the 48 Bronze Saints. He is protected by the Pegasus Constellation so he wears the Pegasus Cloth. He is Tenma's reincarnation.
When Masami Kurumada was in the process of creating Saint Seiya, he gave Seiya the name Rin at first, since Kurumada was going to title his manga "Ginga no Rin". However, as Kurumada continued developing his manga, he decided to change the name to Seiya, which was more fitting. First he spelled the name with the kanji that meant "Holy Arrow", to relate it to Seiya's condition as a Saint, but later decided to use the kanji that meant "Star Arrow", to emphasize the constellation and mythological motif. Finally, he changed his manga title as well, to Saint Seiya, once he fully developed the concept of the Saints. Also, Kurumada stated that one of the first ideas he conceived for Saint Seiya was the Pegasus Meteor Fist. Since his manga was going to use the constellations as a very important and ever-present theme, he wanted his protagonist to have a special move that would be like a shower of meteors.
When Kurumada designed Seiya's likeness, he was inspired by Takane Ryuuji, the main character of his hit manga Ring ni Kakero, which he created 9 years before Seiya. Most protagonists of Kurumada's works bear a resemblance to Ryuuji, because Kurumada subscribes to the revered Osamu Tezuka's Star System technique.
The reason Masami Kurumada chose the Sagittarius Gold Cloth as the most powerful of the Gold Cloths is because of its symbolism in relation to Seiya. In the Japanese language, Seiya means "star arrow", a metaphor for "meteor", and Sagittarius represents an archer, so Kurumada thought it would be a perfect match for Seiya, especially since he already had in mind that the Sagittarius Gold Cloth would eventually be worn by Seiya in certain parts of the manga. Hence, Seiya's zodiacal sign is Sagittarius, since in Kurumada's canon, a Gold Cloth bearer's sign must match the Gold Cloth he represents. The Pegasus Cloth is one of the Bronze Cloths. Armor of Pegasus in original state as delivered by the Sanctuary. This armor has the same features of the original armor From Seiya , but there are differences. His armor was destroyed by Hades Alone.
After the fight he had with Virgo Asmita , Hakurei restores Tenma's armor with the blood of Virgo Asmita. Its format is very similar to Seiya's 3rd armor, but he carries rosary he had received from Sasha.
After training he had against Gemini Defteros, he restores his armor, but only changes the arms of his armor. His armor later reaches the golden glow of the Gold saints, as happened to Seiya, when faced with the specter Owl Partita, his mother.
Thanks to the rosary he received from Sasha, Tenma did, once, move your armor by Kamui alone and for a few moments. In chapter 192, Kamui Tenma finally gets with the help of his mother, Partita, which was not a ghost, but rather the messenger owl of Athena, which had the mission to protect him and guide his soul in the Holy War of 1743.
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