The patriarch of the Yamai Syndicate, a gang based in Honolulu, Hawaii, appearing in Like a Dragon 8. Born August 19, 1973. Blood type O. He was once a member of the Tabata Family, a direct subsidiary of the Tojo Clan. However, about 30 years before the main story, he fell in love with the wife of Patriarch Tabata. He ended up taking the fall for killing his own patriarch, was expelled from the clan, and fled the country, eventually washing up in Hawaii. He is so sensitive to the cold that he wears a heavy coat even in tropical Hawaii, and he uses a crowbar in combat. He is always calm and collected, though he lets his guard down around the hostesses and members of his own turf. Furthermore, he holds a deep admiration for Kazuma Kiryu, who was once a legendary figure in the yakuza world, and shows an intense obsession with him up to a certain point. He refers to Kiryu as "Kiryu-san." His first impression is poor due to his treatment of his subordinate, Eric Tomizawa, but contrary to his outward personality, he is well-respected by his organization and the local community. When Tomizawa tried to attack him, the hostesses (who seem to be older women, suggesting his preference) protected him, saying they wouldn't forgive anyone who laid a hand on Yamai. When he tried to leave Hawaii, his underlings sent him off in tears, shouting that they would wait for their "Patriarch" to return. He is a charismatic man who hides a good-natured side, responding with things like "Don't die until I get back." However, he is the type to put his full effort into harassing those he dislikes, regardless of profit or past grievances, showing a rather spiteful side. Technically, he is no longer a yakuza, so his group is the "Yamai Syndicate" rather than a "Yamai Family," but his men insist on calling him "Patriarch" and referring to themselves as "family members." He used to correct them every time, but since they never stopped, he eventually found it too bothersome and has left it alone lately. During his time in the Tabata Family, he was in love with the Patriarch's wife, Yui Tabata, but she was also having a secret affair with the Captain. At one point, to hide her relationship with the Captain, Yui asked Yamai to kill her husband, the Patriarch, making it look like self-defense. Yamai accepted the request with a sliver of hope that it might win her heart. The plan went as expected, but immediately after the murder, Yui betrayed him, claiming he killed the Patriarch and then tried to attack her, forcing Yamai to flee. While on the run, he worried about Yui and went to check on her in secret, only to see her acting affectionately with the Captain in public. This sight broke his spirit. This incident triggered a permanent case of the "chills" (the reason he wears a coat constantly). He then fled to Hawaii to escape the Tabata Family and the police, eventually forming the Yamai Syndicate with local Japanese-Americans.

Originally an honest taxi driver, he had a pregnant girlfriend named Mary. However, Dwight Mendez, the leader of the Barracudas, framed the innocent Tomizawa for a crime they committed. The Barracudas had ties to the local police and judiciary, leaving Tomizawa powerless; he accepted a five-year prison sentence for a crime he didn't commit. As a result, Mary suffered a miscarriage from the stress and disappeared after visiting him once. He doesn't resent Mary for vanishing, instead blaming himself for the hardships he caused her. However, he harbored a deep-seated hatred for the Barracudas, who ruined his life, killed his unborn child, and made Mary miserable. He went as far as obtaining a gun to seek revenge and found Dwight. Despite having a chance to kill him at the cost of his own life while Dwight was off-guard, he lost his nerve at the last second. This failure caused him to become completely cynical and delinquent. The debt he incurred during this time was held by the Yamai Syndicate, leading him to act as one of Yamai's henchmen.