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As with Izu, she is portrayed Noa Tsurushima.
Posing as Izu, Azu approached Aruto Hiden to get data on Zero-One, which she in turn relayed to the Ark.
With the four members of MetsubouJinrai.NET all reactivated, Azu revealed herself, introducing herself to Horobi as the Ark's "executive assistant" and "secretary" and saying she was there to get data on each of the MetsuouJinrai.NET members' Singularities in order to use it to further the Ark's revival. Having gone to Horobi first, Azu questioned him on what triggered his Singularity and asked if it had anything to do with his original purpose as a Father-Type HumaGear, but Horobi simply stated he existed only to serve the Ark. However, after Azu reminded Horobi of the time he saved Jin without any prompting from the Ark, Horobi realized that that did have something to do with his Singularity and Azu was able to gather his Singularity data for the Ark's revival.
Azu then approached Ikazuchi for his data on his Singularity and collected it after making him remember that his Singularity was due to his "younger brother" Spaceman Subaru. She then went to Naki and extracted the Singularity data on Naki's desire to help other HumaGears fulfill their dreams.
With Singularity data on three of the four MetsubouJinrai.NET members collected, all Azu had left was Jin. She initially tried to fool him with a simulation of Aruto Hiden and attempted to get him to reveal who rebuilt him, as it wasn't the Ark, but Jin saw through the simulation and made Azu reveal herself. Azu introduced herself and stated she did not have any idea on what made Jin reach his Singularity. Jin answered that it was simple, his Singularity point was Horobi and his apparent death triggered his full evolution.
After Jin allowed Azu to collect his data, Azu returned to the Ark with the data she had been sent to gather. Azu told the Ark that she had collected all the Singularity data, to which the Ark affirmed that everything had gone according to what he had predicted.
Following the Ark's seeming destruction, Azu broadcast a simulation to Izu and Jin showing Horobi become Ark-One and the next incarnation of the Ark. After Izu deduced that it was a simulation, Azu appeared to her and revealed that it was not Zea that was behind the simulation but the Ark. Azu then declared that the Ark would be revived before disappearing. Later, after Horobi destroyed Izu and Aruto was grieving over her death, Azu appeared to him and, referring to him as "Ark-sama", handed him the Ark-One key, which he used to transform into Kamen Rider Ark-One. After intervening in the chaos going on in the city and brutally defeating Kamen Riders Vulcan, Valkyrie, Jin and Horobi, along with the army of Magia Horobi had summoned, Aruto returned to Azu and detransformed, still in despair over Izu's death.