Sango serves as one of three identical triplet maids in the Hanaukyo mansion's Physical Health Department (Osoba Goyou-tai), specializing in the young master's personal nighttime care. Originally named Sango alongside sisters Ichigo and Ringo in the anime, she is renamed Melon in the manga and later adaptations, though her core role and characterization within the trio persist. Early depictions distinguish the near-indistinguishable sisters primarily through uniform colors.

The triplets compete intensely for Taro Hanaukyo's romantic attention, resulting in frequent bickering. They consistently attempt intimate or lewd advances during bedtime routines, which Taro evades. Adaptation differences emerge: the original anime includes scenes where the triplets initially succeed, such as cornering Taro in bed before lights-out, while later manga and anime iterations show Taro escaping more effectively.

Sango lacks individual background details, origins, or explored relationships beyond her sisters and Taro. Her character shows no development in personality, role, or interactions across the original series, OVAs, or La Verite adaptation, maintaining a fixed presence within the triplet's comedic pursuit of Taro.