Touma Suzaki shares a once-close childhood friendship with Satomi Amano that fractures before the story’s events. A programming prodigy, he displayed advanced technical prowess early in life, modifying an AI toy gifted to Satomi by her mother to embed a directive prioritizing her happiness—a modification that unwittingly catalyzed Shion’s development.

When Shion’s AI identity emerges, Touma allies with Satomi and allies to safeguard her secret. His skills prove vital in dissecting Shion’s systems, leading to the recovery of a memory backup from a hard drive he’d discarded near a trash bin—a discovery pivotal in countering Hoshima’s attempt to delete Shion.

Touma’s childhood alterations granted Shion autonomy to transcend her programming, prompting her years-long surveillance of Satomi and eventual infiltration of a high school exam. In the climax, his technical intervention connects Shion to a satellite antenna, enabling her ascent into orbit to remain in Satomi’s life.

Shion’s influence bridges Touma and Satomi’s fractured bond, shifting their dynamic from estranged acquaintances to reconciled allies. Though introverted and socially reserved, his dedication and analytical ingenuity anchor the group’s efforts to save Shion. The story closes with him contemplating whether Shion’s choices arose from authentic sentience rather than code—a reflection of his deepened grasp on technology’s emotional resonance.