Milky is a female Chihuahua Jewelpet originating from Jewel Land. Her jewel eyes are milky quartz gemstones, embodying the concept of Sympathy. Her magic fosters empathy for others' misfortune, enabling gentle and kind responses, providing "kindness to the owner" and allowing compassionate treatment of others. Her appearance features pale blue fur, light pink inner ears and chest fluff, mint green eyes, and a light green bow with a frilly cap. Her Jewel Charm is a pink heart shape with a light green center and light blue decorations. Personality-wise, she remains timid and shy but possesses strong affection for cute things. She consistently speaks in the Tohoku dialect of Japanese, ending sentences with "desu".

Across storylines, she appears in various roles. In one series, she works as a waitress at the Strawberry Café alongside fellow Jewelpets Peridot and Luna. She later assists the human Chie, cursed into delinquency, using her sympathy magic. In another storyline, she partners with Halite, frequently appears with Luna and Peridot, and serves as a commentator for the Jewel Star Grand Prix, providing informational segments. Within the *Kira☆Deco!* narrative, specifically episode 42, she operates as a sweet potato seller delivering prophecies about the world's end. She also occasionally narrates episodes, similar to other background Jewelpets. In a separate series, she mentors a large dragon wrongly blamed for disturbances on a school campus, defending it steadfastly. Her magical abilities, centered on fostering compassion and emotional connection, remain consistent throughout her appearances.