Kozue Yoshikawa is a supporting character in Kyoko Okazaki’s manga River’s Edge, which depicts the turbulent lives of high school students in a bleak industrial suburb of Tokyo during the 1990s. She is one of the most popular girls at school and works as a professional teenage model, her image known beyond the school gates. Behind the polished exterior, however, she battles severe bulimia and a deep sense of isolation, believing that people value her only for her looks and status.

Her personality projects a detached, almost unsettling indifference that masks inner emptiness. Kozue is perceptive and often turns conversations toward philosophical reflections on beauty, human worth, and the artificiality of her industry. She resents being praised solely for her appearance and finds the pressures of modeling suffocating, yet she remains trapped in cycles of bingeing and purging as a way to manage emotional pain. That same numbness makes her morbidly curious about the decomposing corpse hidden by the river, a secret she shares with her two only genuine friends.

Kozue’s primary motivation is to find recognition that goes beyond her surface identity. She longs for connection that is not transactional or image-based. The riverbank and the macabre secret she keeps with Haruna Wakakusa and Ichiro Yamada become a rare space where she is seen as a full person rather than a commodity. Her attachment to Haruna deepens into an unhealthy crush, complicating the trio’s dynamic. Before Haruna entered their circle, Kozue was already one of Ichiro’s few trusted friends, bonding with him over their shared status as outsiders in a hostile social environment. Her family and professional contacts remain distant, leaving her to rely almost entirely on the fragile friendship at the river’s edge.

Throughout the story, Kozue functions as a living emblem of the themes of consumption and the hollowness of celebrity. Her disordered eating literalizes the way she both consumes and rejects the standards forced upon her. Her narrative arc shows brief moments of belonging when Haruna accepts her without judgment, but it does not offer a tidy resolution. She gains a measure of solace and self-awareness through the bond with her two friends, yet she remains caught in her self-destructive patterns. Kozue does not possess extraordinary abilities in a supernatural sense, but her insight into the artificiality of her world and her capacity to question what others take for granted make her a quietly discerning presence in a landscape marked by nihilism and quiet despair.