He was one of the 10,000 players trapped in Sword Art Online, working as a blacksmith in Aincrad. More notably, he was the first player to actually open a shop since the Official Server Service began—something that set him apart from other crafters at the time.
His operation, «Nezha's Smith Shop», is pretty modest: just a street stall with a vendor's carpet set up in Urbus on the second floor. When he first showed up, people pegged him as a blacksmith with genuinely terrible luck, which became his whole thing for a while.
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