Yamazaki was orphaned at a young age in the streets of Okinawa. His life was a miserable and boring existence — with American troops constantly patrolling his town — until he caught glimpse of a well-dressed yakuza boss named Sorimachi. Aspiring to be like the man he saw, Yamazaki left his town and joined the crime syndicate. Eventually, he worked under Sorimachi, the man he admired as a surrogate father, and found happiness for the first time in his life as his bodyguard.
Unfortunately, Yamazaki's uneasiness during a fateful business trip to Osaka alongside his boss marked an ambush from a rival gang, and from there his boss Sorimachi was tortured and killed. The shock of his death gave birth to Yamazaki's insane alter ego.
Although he has little memory of his past after this incident, Yamazaki murdered his boss's rival and fled from Japan to Hong Kong. He continues to be an influential broker, weapons dealer, and drug trader with Kowloon Walled City as his base of operations. He is usually at odds with Hon-Fu, who tries to catch and arrest him in the act.
Ten years later, he joined the Chinese mafia and was hired by Jin Chonrei and Jin Chonshu to protect them and the scrolls of immortality. In his Fatal Fury 3 ending, Yamazaki is arrested by local authorities, yet he beats the police officers around him and escapes. He is presumably still on the run from the law.