I₂, designated Ai, emerges as a second-generation clone of Etsuko—Kei’s deceased lover and a pivotal figure within the clandestine society Fraud. Crafted as an experimental successor to the original "I," her existence defies standard Headmeters protocols, with Fraud’s records conspicuously omitting data on both clones. After escaping Fraud alongside Kei, a Headmeters defector haunted by Etsuko’s death during a prior experiment, I₂ navigates a complex bond with him, blending shared trauma with his protective, near-paternal guidance despite their comparable ages.

Though devoid of standard Headmeters enhancements, I₂ is suspected to embody the "Trigger," a mythic entity capable of awakening and amplifying latent abilities in others. This theory fuels Fraud’s relentless hunt, intensifying as her interactions unveil destabilizing potential. Her compassion surfaces when she rescues a stray cat maimed by Fraud’s topology wall, an act that inadvertently catalyzes her latent powers—empowering the animal to lethally counter the Tuned-man Lyan and temporarily elevating Kei’s combat capabilities to infinite thresholds during clashes.

Her presence provokes confrontations with Fractured agents like K2, a feminized Kei clone driven by narcissistic fixation. Parallels arise between her suspected Trigger traits and Alloy, a higher-dimensional entity that infiltrates hosts to exploit genetic anomalies, though their connection remains undefined. Within Fraud’s hierarchy, I₂ threatens figures like Kuu Ragua Lee, who seeks to transcend his managed existence by exploiting her unmodified, protocol-defying nature.

Anchored by her unresolved ties to the vanished original "I" and Kei’s guilt over Etsuko’s demise, I₂’s journey intertwines survival against relentless threats with existential reckoning—her identity as a clone colliding with her role as a catalyst for upheaval in Fraud’s meticulously controlled timelines.