Sorawo Kamikoshi is a university student in general education at a Saitama-based institution, initially working part-time at a convenience store before funding her expenses through explorations of the Otherside. Her appearance features chin-length black hair that grows to shoulder length and is later cut back, and brown eyes that shift to an unnatural blue in her right eye after an encounter with a supernatural Kunekune. She conceals this altered eye with a brown contact lens in public. She typically wears practical clothing—a red hoodie, white t-shirt, leggings, and trainers—with some adaptations adding red glasses, though these are absent in the original novels.

Introverted and socially reserved, Sorawo prefers solitude after unsuccessful attempts to socialize early in university. Her cynicism and distrust stem from a traumatic background: her mother’s death, and her father and grandmother joining a cult. Their recruitment efforts drove her to seek refuge in abandoned buildings, sparking an interest in true ghost stories and urban exploration. A pivotal incident occurred when a "red person" appeared in a dream during a hotel stay, questioning her need for family. She acquired kerosene intending to burn down her family home with the cultists inside, but they died in a gas-related accident before she could act. She attended university using student loans, often downplaying her past as unremarkable.

Her modified right eye grants abilities including perception of the Otherside’s true forms, detection of glitches as silver lights, identification of interdimensional gates, and the capacity to induce insanity in humans through focused gaze, though she avoids this unless necessary. She also gains proficiency with firearms, starting with a Makarov handgun provided by Toriko Nishina and later "borrowing" an M4 CQBR rifle from military personnel in the Otherside.

Her relationship with Toriko evolves from initial reluctance and jealousy over Toriko’s search for her missing friend, Satsuki Uruma, to a deep bond termed "accomplices," emphasizing a unique intimacy beyond conventional labels. Their relationship becomes physically intimate, described by Sorawo using the term "nue" (鵼), symbolizing a formless connection combining elements of both their names. She interacts with researcher Kozakura, who critiques her social awkwardness but provides pragmatic support, and maintains distant interactions with junior student Akari Seto, whom she finds somewhat annoying.

Character development shows progression from isolation to forming meaningful connections, particularly with Toriko. She confronts her traumatic past and learns to rely on others during Otherside expeditions, demonstrating protective instincts toward Toriko. Her journey includes reconciling her self-perception with external realities, acknowledging her capacity for ruthlessness in survival situations while gradually opening up to Kozakura and others.

Personal trivia includes a preference for horse mackerel nanbanzuke, dislike of soggy leftover fried food, enjoyment of gameplay videos, and a secret desire to own a cat. Her given name combines "sky" (空) and "fish" (魚), while her surname Kamikoshi means "paper" (紙) and "surpass" (越).