Haruka Amami is a cheerful, optimistic, and hardworking idol at 765 Production, often providing emotional support to others. She enjoys karaoke and making sweets, though her cooking skills outside desserts are initially limited. Notably clumsy, Haruka mentions tripping or falling at least once daily. She maintains strong confidence in her idol career and strives to make people happy, though her dedication can lead to emotional vulnerability and moments of self-doubt about her passion, sometimes resulting in tearful breakdowns where she questions her happiness and purpose.

Haruka corresponds to a miniature Puchidol named Harukasan, resembling her. Discovered by Iori Minase in a temple during rain in Episode 11, Harukasan multiplies rapidly when exposed to water. She avoids bright sunlight and becomes aggressive if fed snacks after midnight. Contact with water can also cause her to grow gigantic or shrink dramatically. Misplacing her ribbons drastically shifts her personality to dark and demonic. Harukasan frequently causes comedic chaos, like scavenger hunts disrupted by her multiplied or enlarged forms.

Haruka insisted on naming the Puchidol after herself, though their interactions remain primarily situational comedy. Across media, Haruka acts as a genial, occasionally emotionally complex idol, while Harukasan serves as a source of supernatural humor and mishaps. Their stories focus on episodic incidents rather than overarching growth or backstory development; Haruka's background and Harukasan's mysterious origins receive limited exploration.