Chitose Naruse, a second-year Houshou Private High School student and Class 2 president, has a slim frame, fair complexion, and light brown eyes accentuated by red-rimmed glasses. Her long brown hair flows into twin braids reaching her thighs, fastened with yellow clips. She dons a mustard-yellow blazer over a white undershirt tied with a red ribbon, paired with a blue skirt, thigh-high black socks, and brown outdoor shoes. Stranded on Little East Island, a giant crab destroys her underwear, leaving her without temporarily; she later adapts by knotting her vest and shirt to bare her midriff.

A principled leader, Chitose earns peer respect through unwavering ethics and bold opposition to misconduct, particularly sexual impropriety. Her disdain for manipulative classmate Misuzu Jinno stems from uncovering Misuzu’s transactional affair with a teacher, fueling their rivalry. Though altruistic to a fault—prioritizing others’ safety even amid hostility—her trust remains guarded, shaped by this betrayal.

After a plane crash strands her group on the island, Chitose organizes survival efforts, leveraging Mutsumi Oribe’s entomological knowledge. Captured early by a giant wasp and anesthetized, she requires Mutsumi’s rescue. Later, incapacitated during a parasite inspection, she endures harassment from Misuzu, who exploits her vulnerability. These trials underscore her tenacity and unyielding resolve to shield others.

Evolving from an authoritative figure to a frontline combatant, Chitose fashions a bamboo sword to battle encroaching insects, embodying adaptability and grit. She navigates moral quandaries and betrayals, persistently rallying peers to collective action—convincing even reluctant classmates to aid rescues. Her bond with Mutsumi intertwines mutual dependence with subtle romantic tension, though its contours remain undefined.

Confronting colossal spiders, centipedes, and human frailty, Chitose intervenes to protect Mutsumi from assault and mobilizes the group against threats, her leadership affirmed through unity rather than force. This contrasts sharply with rivals like Atsushi Kamijo, whose self-interest triggers disaster. Tested by violence and treachery, she upholds her ideals while pragmatically compromising to preserve cohesion, as when sparing disruptive peers or defying opposition to free Mutsumi. Her journey weaves idealism with survival-driven pragmatism, steadfastly defending her values against the island’s relentless crucible.