Tokio

Tokio is a girl residing within the walled, closed facility known as Kōgen Gakuen, sharing a close bond with her companions Yamimiki and Kona. Her gender was initially ambiguous due to her androgynous appearance and the institution's gender-neutral educational approach; she later gives birth to a child together with Kona. Naturally pure in spirit and filled with curiosity toward the outside world, she demonstrated a defensive ability called 'hardening' when the academy came under attack. As the pivotal figure connecting both the past and future timelines of the story, she stands at the very heart of the narrative.