Akemi Mikihara is a twelfth-grade student and classmate of protagonist Kenta Kogure. She possesses long, straight blond hair and gray eyes, a slim teenage physique, and pale skin. Alternative descriptions note blue eyes and shoulder-length hair. Her typical appearance features her school uniform with a string ribbon tie; she is also depicted in a swimsuit, revealing her medium breast size.

Serving as captain of the school tennis club, Akemi secretly engages in a romantic relationship with the club's faculty advisor. This hidden involvement fosters her secretive and dishonest nature. Her personality is characterized by cowardice, selfishness, and talkativeness. She maintains a friendship with student Mio Serizawa while harboring a notably antagonistic relationship with teacher Takashima Kumi.

Her narrative role centers on being trapped with others inside an abandoned school building. The central conflict involves navigating the confinement, avoiding capture, and seeking escape.