Born from melon bread infused with love flower nectar, Melonpanna serves as a heroic ally to Anpanman, assisting him on patrols and deliveries. Her appearance features a melon bread head, a dark green uniform accented by a light green belt, gloves, and boots. A distinctive cape with a green top and orange underside flows behind her, while a cursive "m" insignia adorns her dress.

Kindness, honesty, and a gentle nature define Melonpanna. She demonstrates profound loyalty to her allies, particularly regarding Creampanda as a younger sibling despite their lack of biological ties. However, distressing situations, such as encounters with the bandage-wrapping Houtaiman, reveal her vulnerability.

Melonpanna shares the common bread-hero ability of flight. Her signature "Melo-Melo Punch" pacifies foes by inducing affection or dizziness, and can awaken those in deep sleep. She also produces "Melo-Melo Juice" from her head, effectively cleansing allies affected by Baikinman’s blackening attacks.

Critical weaknesses include a dependence on melon juice for energy; depletion causes her to faint. Psychologically, she is vulnerable when her biological sister Rollpanna's "blue heart" activates, potentially causing Melonpanna to lose her sense of self. She deeply admires Rollpanna, though infrequent meetings bring loneliness, and uniquely calms her sister during instability. Melonpanna holds a sisterly bond with Anpanman, who supports her educational growth. She treats Creampanda with protective, nurturing affection.

Melonpanna debuted in episode 200, "Melonpanna is Born," appearing subsequently in television episodes, films, and edutainment specials. Her consistent role as a supporting hero emphasizes interpersonal dynamics, particularly her relationship with Rollpanna, highlighting themes of familial bonds and emotional resilience.