Nachi was one of the 100 orphans gathered together by Mitsumasa Kido and sent off to become Saints.  He trained in Liberia to earn the Wolf Cloth.  His only known attack is "Dead Howling." 
 
During the Galaxian Wars tournament, Nachi stopped Ikki from killing Unicorn Jabu, claiming the fight was his according to the tournament draw.  Ikki said he didn't care about the tournament, but agreed to fight anyway, defeating Nachi with a single Genma Ken attack.  Caught by the illusion, Nachi believed that Ikki's fists were giant and that he was being crushed. 
 
After his loss, he returned to Liberia for more training, and was not seen again until he arrived at Sanctuary to help protect Athena until the other Bronze Saints could defeat the Gold Saints. 
 
When Seiya and the others fought Thanatos in Elysium, Nachi risked his life to shield Seiya's sister Seika from Thanatos' attacks.