Takayuki Yagami

Writer and executive director Toshihiro Nagoshi (left) used multiple detective stories as inspiration for Yagami's character, most notably Paul Newman (right) in The Verdict.

Since the game Yakuza 6: The Song of Life concluded the story of Yakuza series protagonist Kazuma Kiryu, the Ryu Ga Gotoku Studio game developers wanted to create a distinctive character for the story. At the behest of producer Kazuki Hosokawa, the team decided the character should be a detective.[1] The biggest influence was the Paul Newman film The Verdict, in which Newman's character Frank Galvin suffers a crisis similar to Yagami's in regards to his career as a lawyer.[2] In order to a stark contrast between Kiryu and the new protagonist, the staff wanted to develop Yagami as a more relatable character, with his fall from grace and gradual redemptive arc designed to appeal to players. Due to the popularity of detective stories, Ryu Ga Gotoku Studio wrote Yagami as a man who would become more knowledgeable alongside the player as the game progressed.[3]

Sega described Yagami as "a man of conviction who fights for his beliefs, despite the overwhelming despair surrounding him".[4]

Executive director and writer Toshihiro Nagoshi said the detective idea drew on multiple influences, primarily Korean films.[5] Because there are few games based on detective dramas, Hosokawa wanted Yagami to stand out but recognized creating a new character is a major challenge. To make a protagonist who would be a fitting successor to Kiryu, Hosokawa wanted Yagami to be "more grounded to fit the noir vibe". He also said:

"When you’re writing a story and there’s a really solid character that’s been around for a long time, the character dictates what happens next. In contrast to that, with Yagami, at the start of development we didn’t really have anything attached to him at all. It was a challenge, but also an opportunity for a development team that has been working so long on the same series."[1]

The staff wanted the protagonist to have a deep connection to the city. To emphasize this, they introduced a gameplay mechanic known as the Friendship System, allowing Yagami to befriend and form bonds with the residents of Kamurocho.[6] The developers used the main story to explore facets of Yagami's personality, using sidequests to please fans wanting a balance between seriousness and comedy. Hosokawa regarded the friendship system as one of his favorite parts of Judgment due to the bonds Yagami forms with other characters. As a result, Hosokawa believes that a Judgment sequel would have to remain in Kamurocho due to Yagami's strong connection with the city and its people.[7] In contrast to previous Yakuza protagonists, who are often only visitors to Kamurocho, Yagami was written as a civilian resident in the city, allowing his social life to be further explored.[3]

Localization producer Scott Strichart said though fans might miss previous Yakuza characters, like Kiryu and Goro Majima, he hoped they would be receptive to Yagami, describing him as "his own person – super smart, a razor-sharp wit, and a guy who harbours his own flaws, too".[8] The relationship between Yagami and his ex-lover Mafuyu Fujii was changed during development because Nagoshi found the romance spoiled the thriller aspects of Judgment.[9] Nagoshi also expressed doubts about the game's popularity in English-speaking countries because Takuya Kimura is not popular in Western regions.[9] Following the release of the game, Sega staff felt that if there should be a sequel to Judgment, Yagami and his partner Masaharu Kaito would retain their lead roles and would still be set in Kamurocho.[10]

Takuya Kimura served as a face model to Yagami as well as Japanese actor.

Early in the development of Judgment, the developers considered using a famous actor to portray Yagami, deciding upon Takuya Kimura. Nagoshi was afraid audiences would accuse them of toning down the character due to Kimura's popularity. However, Kimura was open to the team's suggestions and worked with the developers to hone the character. Yagami has more spoken dialogue in Judgment than Kiryu had in any individual Yakuza game. Sega was pleased with Kimura's performance, noting he needed far fewer retakes during recording than they anticipated. Some lines were rewritten to better fit Kimura's delivery, but the writers ensured these changes would not deviate from Yagami's personality. The game's dialogue was recorded in chronological order so players would feel Kimura's voice evolving as Yagami's character develops during the story. Kimura enjoyed his work on the game, and Nagoshi remarked on Kimura's quick response to his messages. In contrast with previous Yakuza titles, the game was not recorded until after the whole scenario was written, which helped Kimura and the other actors.[11] Yagami's character was revealed alongside the Japanese marketing of the game in September 2018. Sega stated that Kimura "more than 1,000 minutes of voice recording time for his lines". As a result, the company aimed to bring a major appeal in the protagonist.[12]

Nagoshi also expressed doubts about the game's popularity in English-speaking countries because Kimura is not popular in Western regions.[9] The game also references other parts of Kimura's career, such as the dialogue line "Chotte mateyo" (Hey, wait a minute!), a line spoken by Kimura's character in the 1997 television drama Love Generation and Yagami's use of multiple outfits like Kimura.[13]

Based on his previous knowledge of the Yakuza franchise, Greg Chun was surprised and pleased to be selected to voice Yagami in the English-language version of Judgment.[14] Yagami's voice was meant to make him sound like a "bona fide badass" regardless of language, something the localization team believed they succeeded at.[15] Chun found his work on the game gratifying, saying, "it really did require me to let go of the tricks that you use to push a performance through, and I really did need to fall back on authenticity and genuine groundedness".[16] Chun found staying faithful to the spirit of the Japanese version challenging, but enjoyed portraying Yagami's blend of seriousness and comedy. He said having to scream in certain parts of the game was difficult.[16] Chun was surprised by the depth of Yagami's character arc, considering his work on the game an unforgettable experience.[17] He found the character easy to connect with because of his realistic characterization.[18]

Yagami's fighting style was inspired by Chinese martial arts.[19] Ryu ga Gokotoku Studios developed multiple techniques for Yagami. While the team had experience thanks to the main Yakuza game, they felt that Yagami should have own new unique moves. This was provided by the fact that Judgment is noir game and thus were restricted to techniques that fit the genre. This was balanced by giving Yagami his own detective skills not present in any of their previous works.[20] Nagoshi wanted to make Yagami's moves entertaining in order to make the player relief stress from the dark narrative but did not want him to use over-the-top fighting techniques. Yagami was given the Parkour moves like the wall kick with the intention of making the character being easy to control. Yagami's fighting style was inspired by Asian movies with a stylishness based on Kung Fu style and Parkour moves at the same time. In order to fit the actor behind the character, Nagoshi claimed that he drew parallels from Power Rangers-like characters. This further made Nagoshi felt Yagami's character would be fitting to Kimura.[21] In the original Japanese version of the game, Yagami's fighting styles are known as Flash (一閃) and Waltz (円舞) stances. Sega changed them for the Western release to crane-style and tiger-style stances since they found order to these two words more common for English speakers.[22][23]