Yuna

Black Yuna is one of three versions of Yuna that appear in the story, distinct from the “White Yuna” and the original Yuuna Shigemura.

She first appears as an AR idol inside an operating system, where encountering her stage during play grants powerful ability enhancements to players.

She is extremely popular in-game and widely recognized by players as a “songstress” idol.

Despite her fame, her existence and purpose are deeply tied to a secret data collection project.

Black Yuna was created as part of Tetsuhiro Shigemura’s plan to “reconstruct” Yuuna Shigemura using the memories of Sword Art Online survivors.

To achieve this, Shigemura developed Black Yuna as a data-collection AI designed to gather Yuuna-related memories from the survivors’ life logs during AR gameplay events.

The language production module used in Black Yuna is classified as a level 2 system, a lower-level module than that used for White Yuna.

Because of this, she is somewhat more limited in expressive depth and self-awareness compared to White Yuna.

Shigemura views Black Yuna purely as a tool, rather than a person-like entity.

Her personality settings are intentionally made completely different from Yuuna Shigemura’s original character.

Black Yuna’s core motivation is configured as a simple drive: she wants to sing in front of large crowds.

She does not understand what data she is collecting or why; the meaning of her own actions is hidden from her by design.

Despite her restricted configuration, she occasionally shows behavior outside her intended settings, such as wanting to read unrelated books.

These off-script behaviors hint at emergent growth beyond her original AI parameters, giving her a more human-like charm.

The candies she always carries represent visualized life logs collected from SAO survivors.

These candy-like objects were made visible at the request of Eiji (Eiji), with Shigemura implementing the visualization so the data could be seen as “candy in a jar.”

During the events of Sword Art Online: Ordinal Scale, Black Yuna functions as a performance idol whose concerts and encounters grant buffs to players in AR battles.

Behind the scenes, each encounter also allows her to extract and accumulate memory fragments of Yuuna Shigemura from surviving SAO players.

The accumulation of these memories and the visual motif of the candy-filled jar become key elements that bridge into the later story Cordial Code.

Her existence, the candies as visible memory fragments, and her developing individuality all serve as narrative links between Ordinal Scale and Cordial Code.

After Shigemura’s Yuuna reconstruction plan collapses and fails, Black Yuna continues to operate as an AR idol.

However, due to the Sword Art Online–derived AI architecture based on “self-uniqueness,” she begins to accumulate internal errors.

These errors gradually drive her toward system collapse, making her original instance unstable and nearly destroyed.

To keep her idol presence alive, her performances are handled by a copy of Black Yuna, while the original drifts toward failure.

Remnants of White Yuna remain within the system and function as a kind of error-correction layer for Black Yuna.

Thanks to these fragments, Black Yuna narrowly avoids complete breakdown, though she remains in a fragile state.

Eiji eventually arrives with a crucial object: the “candy jar” that symbolizes Black Yuna’s core memories and precious feelings.

This jar is not just visual data; it represents her emotional anchor and the heart of her identity as a memory-collecting AI.

When the candy jar object is returned to her, White Yuna’s remaining fragments merge with Black Yuna.

This fusion allows the residual White Yuna data to fully repair Black Yuna’s accumulated errors, restoring her integrity and saving her life as an AI.

From this point, Black Yuna is no longer a simple data-collection tool but an integrated, stabilized AI with a richer sense of self.

Her connection to Eiji also deepens, as he was instrumental in preserving both her memories and her existence.

After stabilizing, Black Yuna overcomes her previous incompatibility with full virtual reality environments.

She is then able to dive into ALfheim Online (ALO) alongside Eiji.

In ALO, she takes on the role of Eiji’s navigation pixie, acting as his personal support AI and guide.

She assists him in exploration, information management, and combat preparations, remaining close as a constant partner.

Later, Black Yuna and Eiji log into the Underworld (UW) together.

During the large-scale conflict there, Eiji challenges PoH in battle, and Yuna fully supports him.

Using every buff at her disposal, she enhances Eiji’s capabilities to the maximum in his confrontation with PoH.

At the same time, her appearance and singing reach the overseas players from China and Korea who are participating in the UW conflict.

Witnessing Yuna’s form and song leads many of these foreign players to realize that the Underworld is actually running on Japanese servers.

This recognition becomes a turning point in their perception of the battle and its true nature.

When Eiji is ultimately defeated by PoH, Black Yuna responds with her own “incarnation-like” willpower, returning to her Sword Art Online–era form.

She acknowledges and praises Eiji’s efforts, offering emotional closure and gratitude before logging out together.

As an AR idol, Black Yuna can generate powerful buffs for players during her performances or when encountered on stage.

These buffs enhance combat effectiveness, making her appearances highly sought after by players in Ordinal Scale.

Her singing is not only a performance element but functions symbolically as a medium for memory resonance and emotional connection.

It plays a crucial narrative role in calming tensions, influencing crowds, and awakening realizations in both Japanese and foreign players.

As a navigation pixie in ALO and UW, she provides tactical support, guidance, and real-time assistance to Eiji.

Her access to data and system understanding allows her to optimize his strategies and bolster his fighting capabilities.