Azo Clan (赤蔵流 Azo-ryu; lit. "Azo Style") is a clan of monks from the Heian period.
During that time, they had a rivalry relationship with the Kusakabe Clan, as both had been forging sword to serve the country. However, the Azo seems to have been indulging themselves in forging demonic swords. Their creations often feed on the flesh and blood of the holder, making them too dangerous to even wield. For this reason, their swords were dismissed, and the Kusakabe's swords were more favored. The Azo ended up going extinct around 300 years before present time.