Ms. Aki is an adult woman with long, straight dark brown hair held by a pink headband and round glasses framing her yellow eyes. She is typically depicted barefoot, wearing a white lab coat over a white shirt with a low neckline emphasizing her chest.

Her initial appearance occurs briefly in the original world before the students' teleportation, where she faxes documents while dressed differently, indicating she wasn't transported alongside them initially. Later, she emerges from the sea in the drift world, announcing the end of their "fun and games" and informing the students they can never return home. She claims to be sent by God, whom she identifies as the school's Principal.

Ms. Aki manipulates the student group dynamics by asserting their displacement resulted from Nagara's "Escape" ability—his subconscious desire to leave the original world. Simultaneously, she elevates Asakaze, labeling him the guardian of "This World" who alone possesses the potential to evolve and protect others. This strategy fractures the class: Asakaze and several others align with her, while Nagara, Nozomi, Mizuho, and Rajdhani pursue independent paths home.

Her interest in Asakaze is purely instrumental; she values only his gravity-manipulating "Slow Light" ability, disregarding him as an individual. Her flattery exploits his desire to feel uniquely significant, a vulnerability noted by other students. Her motives for fostering division or leveraging student abilities remain ambiguous, though her arrival intensifies ideological conflicts about survival and purpose within the drift world.