Kayo Gōtokuji is a first-year high school student and a main character in Survival Game Club!. She has a pale complexion, short light blue hair, and violet-blue eyes, and is the shortest member of the club. Kayo is an otaku with a deep passion for cosplay, and her primary interest lies not in survival games themselves but in the opportunity they provide for her to dress up in various costumes. She is an accomplished seamstress who makes her own costumes, with her favorite and most frequently worn outfit being a cosplay of Jill Valentine from the video game Resident Evil 3.

Kayo displays a calm and stoic demeanor, rarely showing strong emotions. Despite her quiet and disinterested exterior, she possesses a remarkably high IQ of 160 and often surprises others with her analytical mind and strategic thinking. While she may seem indifferent to the club's activities, she is a dedicated and valuable member of the Survival Game Club, where she typically wields two Ingram MAC-11 submachine guns in an akimbo fashion. Her expertise with these weapons makes her a formidable markswoman during the club's mock battles.

Though she lacks a personal interest in airsoft combat, Kayo's involvement is secured by the creative possibilities it offers. Her dedication to cosplay is such that she is known to carry a large bag of related supplies and can quickly produce costumes for others on a whim. In one instance, she created a ghillie suit for camouflage, and despite its bright red color that would logically make her stand out, she remained completely unnoticed by the crowd, demonstrating a bizarre but effective form of stealth. Her relationship with the other club members is defined by her quiet support and her role as the team's genius, often providing factual insights or unorthodox solutions. She is also known to be an anime enthusiast, expressing familiarity with series that other members discuss.