Ryōko Sakaki, a dedicated student at Tōtsuki Culinary Academy and longtime resident of Polar Star Dormitory, draws her culinary identity from the Sakaki family’s renowned koji and fermented goods shop. Trained in fermentation techniques since childhood, she masters dishes like shio koji-marinated specialties and soy natto creations. Her composed, nurturing demeanor earned her a “big sister” reputation, providing steady guidance to peers such as Yūki Yoshino and Megumi Tadokoro during high-pressure events like the Friendship and Rapport Training Camp, where her calmness contrasted sharply with widespread panic. Sporting waist-length fuchsia hair—later cropped to a chin-length bob—she dresses in Tōtsuki’s standard uniform or crisp chef’s whites while experimenting in her dorm-adjacent fermentation workshop. This space produced ingredients like fermented rice juice, occasionally featured in dormitory gatherings. At the 43rd Annual Autumn Election, her seemingly humble soy natto curry rice dish stunned judges with its intricate flavor balance, though she narrowly missed advancing. Undeterred, she later aided Sōma Yukihira by fermenting Pacific saury for his competition entry, embodying her collaborative spirit. This ethos extended to casual dorm life, from ping-pong matches to mentoring newcomers. When Azami Nakiri’s regime disrupted Tōtsuki, she aligned with the rebel faction, contributing to collective strategies during the Regiment de Cuisine. Post-conflict, she persisted as a stabilizing force within Polar Star, prioritizing camaraderie and shared growth among residents.