Kaneko Sonoka is a secondary character in the anime, serving as one of the self-proclaimed bodyguards of Aki Adagaki and holding the position of Vice President of the Yasaka High School Student Council. She is a student in her third year, which makes her older than Aki. Her full name in Japanese is written as 金子園香, and the kanji for her surname relates to concepts of gold or metal and child, while her given name relates to garden and fragrance.

In terms of appearance, Kaneko is a fairly short girl with a cute demeanor. She has dirty-blonde hair that reaches her chest, with two straps tied up by pink ribbons into ring-like shapes. Her eyes are pink in color. She wears the standard Yasaka High School uniform, which consists of a pink shirt, a black vest displaying the school symbol, a striped yellow skirt, and a blue and yellow ribbon.

Kaneko's personality is characterized by a calm and optimistic nature. However, beneath this composed exterior, she is also shown to be quite manipulative and persistent, unwilling to stop until she achieves her desired outcome. This combination of traits makes her a more complex figure than her cheerful appearance might initially suggest. She is notably susceptible to the strategies of Kanetsugu Gasou, another key character in the series.

Her primary role in the story is as a member of Aki Adagaki's informal entourage of bodyguards, a group that also includes Mari Mizuno and Kikune Kiba. As the student council vice president, she holds a position of some authority within the school's hierarchy. Her background includes a connection to the protagonist, Masamune Makabe, that dates back to their childhood, a shared history that becomes a significant plot point. This past connection reveals that her feelings for him are genuine, as she cares for him for who he truly is, contrasting with the more superficial motivations of other characters.

A notable aspect of her character development involves a hidden health condition. She is portrayed as being sickly, with a medical issue that causes her to experience seizures and requires her to take various vitamins and medications. This vulnerability adds a layer of depth to her otherwise manipulative and persistent personality. Her advances toward Masamune are ultimately rejected, which serves as a key emotional beat in her narrative arc. Her primary relationships in the series are with Aki Adagaki, whom she serves as a bodyguard, and with Masamune Makabe, for whom she harbors romantic feelings. Her family was also apparently close to Masamune's family in the past, explaining their childhood encounter. She does not possess any supernatural or combat-oriented abilities; her notable traits are her social manipulation skills and her determined, persistent nature.