He is portrayed as a high school student who moves to the countryside region Inaba away from his city home, to live with his uncle Ryotaro Dojima and cousin Nanako while his parents are busy working.

Yu was designed by Shigenori Soejima who aimed to create an ambiguous character who could appeal to most players by way of reflecting several feelings towards them and through his mannerisms.

Yu has been positively received by critics, with his characterization, social life and being the subjects of praise due to his portrayal as a mostly silent teenager whose few lines are related to the plot and in some cases, a source of witty comedy.

Character designer Shigenori Soejima made Yu with the idea that his entire personality be decided and portrayed by the player's in-game actions and decisions.

[4] In contrast to the Persona 3 protagonist who was seen as "shy" and "cute", Yu Narukami is meant to have far more different design which resulted in a smaller hair and "cool" eyes that in order to fit with the fact glasses he wears in TV World.

[5] In retrospective, Hashino claimed that Yu was written as a character who would be the driving force of the narrative, most notably to contrast how he is originally from a city with his coming to a country.

[8] Izanagi's design was meant to convey a "manly" feeling but the artist felt it would be too cliche if the Persona looked like a high school student.

The aspect of youth psychology was implemented in Izanagi's knife as in previous times, it was accepted that grown man would be allowed to wield weapons in the middle of the city.

Hashino elaborated that it was possible to create such an attitude by having the fighting solely done by the Personas, thus establishing Yu as an emotionally strong character—something which "would have lost its significance if he was given a weapon.

[2] Upon learning of the Midnight Channel's connection with the murders in Inaba, Yu gains access to the TV world, where he investigates the case alongside his friends and is appointed as their leader as a result of his experience.

[16][17] There he awakens his initial Persona, Izanagi (イザナギ), a swordsman wearing a black coat, which he uses to fight embodiments of humans' negative feelings, the Shadows.

[19] This is tied with the Social Links (Community (コミュニティ, Komyuniti) in Japan) mechanic: each bond Yu makes with other characters grants him access to more and much stronger Personas,[20] each named after one of the Major Arcana of the Tarot deck.

[22] After closing the serial murder case, Yu learns he gained his powers from the goddess Izanami who had been posing as the Moel gas station attendant and aims to transform people into Shadows.

[23] Yu defeats Izanami by transforming Izanagi into Izanagi-no-Okami (伊邪那岐大神, Izanagi-no-Ōkami), representing The World, thanks to the power he gained from his many friends through Social Links.

[25] In the fighting game Persona 4 Arena, set two months after the events of Persona 4, Yu returns to Inaba for a holiday reunion, but must go to the TV World alongside his remaining friends to investigate a fighting tournament promoted in the Midnight Channel, while finding some of their missing friends and acquires help from their predecessors, Kirijo Group's Shadow Operatives.

[26][27] As the group is unable to find the mastermind behind the competition, the Investigation Team and Shadow Operatives decides to search for him behind his kidnapping Aigis' older sister android Labrys.

Aiyakyuu also mentioned having trouble making the fight scene between Yu and Akihiko Sanada from Persona 3 as "Both characters wouldn't easily lose to anyone.

While Yu and his friends initially believe the culprit is a teenager with two split identities named Sho Minazuki, it is later revealed that the mastermind behind the fighting tournaments in the two Arena games is Kagutsuchi, a being that aims to destroy mankind.

[19] In Law, Culture and the Humanities, Ashley Pearson from Griffith University notes that while Narukami shares a similar to role other gaming protagonists involving connections with the player, Persona 4's protagonist and the supporting cast find themselves in conflict with their identities, most the concepts of Personas and Shadows, which gives the player major immersion in the narrative.

The handling of Social Link further explores the idea of immersion as both the player and the protagonist are benefitted from interacting with the inhabitants from Inaba through a notable hero's journey that sends the message of how bonds with others are inescapable and necessary.

[48] Although Narukami can only date women, there were several rumors about him starting a homosexual relationship with Yosuke Hanamura based on data from the original PlayStation 2 game.

When Golden was ported to Steam, mods started leaking lines from Yosuke that imply that the Social Link between the protagonist and him could also lead to a romantic ending.

[57] Narukami and Adachi were compared by the Petra Christian University to Yin and Yang from Street Fighter as they possess contradictory character traits and represent a certain symbol on the society.

[61] Briana Lawrence from the Fandom Post shared similar feelings, stating that the staff "somehow managed to give a silent protagonist a personality that's not only believable, but likable."

"[62] While also commenting how Yu manages to reinforce both the comical and "spooky" elements of the plot, Blu-ray's Jeffrey Kauffman noted he "remains something of a cipher throughout the series" with the possibility of having the viewer relate with him.

Calling him "one of the oddest characters in any work of fiction ever", Eisenbeis found that his lack of backstory made it difficult for the viewer to predict his actions.

"[66] However, he criticised Yu's characterization in Persona 4 Arena and its sequel for being a stereotypical lawful-good hero and less than a bland compared to the new character Sho Minazuki and Rise's development.