- "I've got my own brand of Justice!"
- —Masayoshi Tanimura
Masayoshi Tanimura is a fictional character from the Yakuza series who made his debut in Yakuza 4. He's voiced by and his face likeness is based on Hiroki Narimiya. He takes his role in Part 3 through the game.
A young mixed Japanese man who somehow endures the prejudices of Japanese society. Tanimura learns that the murder of his father may be related to the corruption in the force and begins a journey to seek out the truth.
Born to a Thai mother and a police officer named Yusuke Kaga, during his time as a detective he made many connections with the prostitutes in the trade as contacts for information. Eventually, Kaga was fired from the force when he was accused of shooting an innocent and got framed for it, Kaga opened up a small coffee shop and continuing helping the prostitutes. At some point of his career, Kaga uncovered a link between the prostitution rings and illegal visas ran by Yuji Katsuura, a politician who runs an organization for the purpose of smuggling women. One of the prostitutes who found out about the link between Katsuura's organization and confided in Kaga, who eventually fell in love for and consummated their relationship, resulting in the birth of Masayoshi. Fearing for the safety of his children, he focused on ensuring both of them were safe by helping Masayoshi's mother escape to Thailand safely while giving the baby to Taiga Tanimura, the former partner of Kaga to ensure that Katsuura would have no leverage. Kaga was soon murdered by Katsuura and Taiga raised Kaga's child and named the child Masayoshi as Kaga wanted a child who had a genuine sense of justice.
Life took a tragic turn when his father was found murdered at the young age of 3 for investigating the Ueno Seiwa Hit when he attemepted to contact Yasuko Saejima as Taiga had a hunch that the hit was way too suspicious in its execution. He spent his life in Homeland as Zhao struggled to raise him in a society that shunned foreigners and Tanimura have seen a great deal of children his age forced to live in Japan without their parents who would end up getting deported. Seeing the aspirations of his father as a skilled detective, he graduated he joined the police force and quickly became a member of the Community Safety department. Knowing his finances cannot support the immigrant children who was left without their parents and knowing what it was like to grow up with a father, he begins illegally gambling and blackmailing smaller brothels to help support them as he could. This quickly netted him a negative reputation of being called the "Parasite of Kamurocho", a reputation Tanimura accepted to ensure other children have the same opportunities as he did.
Tanimura was introduced when he was sent to investigate Arai's homicide of Ihara. Warning Akiyama to run before the law gets him, Tanimura leaves the police scene in time for Akiyama to be held in custody.
Tanimura begins his investigations under Suiguchi's orders and asks Zhao for help.He receives a call from Park, a massage parlor owner saying he may have found Yasuko Saejima. Tanimura finds her only for thugs belonging to Shibata kidnap her and wanted to kill her for the deaths of his lieutenants. Fighting his way through the docks. He finds out that Yasuko has been killing people on behalf of Katsuragi and witness Arai killing Shibata. Leading Yasuko to safety, she tells him the location of the yen requested as Tanimura secures the money and contacts Katsuragi to trade for information.
Meeting with Katsuragi, they discuss the matter on their way as Tanimura pieces together the circumstances of the Ueno Seiwa Shooting and figures that Katsuragi had a bigger role in the events and learns he was the true murderer. As he prepares to depart, Katsuragi orders his men to go to Homeland and kill Zhao and Mei after surrounding Tanimura. He was saved by Suiguchi who deters Katsuragi's thugs from attacking Tanimura and get there in time to save his family and learned Hisai was here waiting as well.
With Hisai's help they find out that Suiguchi was the one who wrote the report and that he had a link to the case as he was the one responsible for the investigation and motives behind the attack. With Yasuko leaving for Okinawa to find her brother, Tanimura attempts to return the money only for Akiyama to decline the offer as he wanted Yasuko to personally return it. He gives him a tip that Mishima, the other surviving thug at Elnard was hiding at the docks. Tanimura faces the true culprit behind the murder of his father as Suiguchi who comes in and kills Mishima to ensure his silence. Defeating his mentor and father figure after lengthy chase. He confronts him in asking about why did he murder his father and cover up the incident. Suiguchi confesses to
being a mole but became a legitimate detective over the years as he enjoyed being a cop despite being sent there as a spy. He also points out that Munakata, the current chief of police was the the one who provoked the events that led to everything that shook the Tojo clan. Suiguchi was murdered by Hisai.
Returning to Homeland to learned that Hisai has committed suicide over killing Zhao and Mei Hua, with Akiyama's help both of them managed to allow Yasuko to get into Purgatory as they try and fail to defeat Kiryu only to learn Katsuragi has already knew where Taiga and Lily were but was forced to stay to tend to their wound.
After learning that Yasuko has died killing Katsuragi, Tanimura and the three go to Millennium Tower to deal with their respective foes as Tanimura defeats Munakata and his retinue of policemen under his direct command.
During the credits, Tanimura returns to his usual gig of being the Parasite of Kamurocho until internal affairs reassigned him out for illegal gambling.
Masayoshi is the youngest protagonist in the game. He appears with ordinary policeman's uniform with black tie and covered by blue jacket. He also wears gray pants, a white belt with a snake motif and brown shoes. He always has an earphone attached to his right ear, because he likes listen to horse races on a pocket radio (kept in his jacket). In the final chapter of the game, he wears a black tuxedo with black pants that similar with his normal outfit.
Tanimura has a sense of justice. He is always caring and always there to help, like his relations with Little Asia. Tanimura is also determined when he was finding the murder of his father, when he is on patrol, he is gambling instead of doing his work, He is also horsebetting and always ignores anyone on sight.
He's a polyglot, being able to speak multiple languages due to his upbringing in Little Asia.
Masayoshi's fighting moves are standard police combat, with influences from aikido and jiu-jitsu. He mainly does parrying and submissions (e.g. bonebreaking) during combat. The end of each of his combos will activate Heat Action. Masayoshi however has low health, and his attacks are slow. He only relies on building up Heat and using combos, as well as using his main technique being the parry.
- He is the first and only character beside Kiryu that get to fight the final battle in main game, which his opponent is Seishiro Munakata.
- In Yakuza 4, protagonists representing the 4 Eastern Gods. Masayoshi Tanimura represents Black Tortoise, as he focuses on defense (dodging) out of the characters and is the most down-to-earth. He also has the thickest coat, representing the Tortoise's shell.