Originating from the "Anpanman" franchise, Melonpanna debuted in Episode 200 of "Soreike! Anpanman." Uncle Jam crafted her using dough infused with the nectar of a "flower of love," imbuing her with inherent kindness and compassion. Her physical form is melon bread, distinguished by a criss-cross pattern on her head. She wears a dark green uniform featuring a light green belt, gloves, boots, and a cursive "m" insignia on the chest, completed by a cape with a green exterior and orange interior. Her face features large green eyes, a small green nose, and orange diamond-shaped markings on her cheeks.

Melonpanna possesses distinct abilities. Her **Melo-Melo Punch** induces temporary paralysis through overwhelming affection or awakens individuals from deep sleep without causing harm. She produces **Melo-Melo Juice** from her head, capable of reversing Baikinman's "blackening" corruption on allies; however, this power fails when Baikinman directly suppresses the goodness in Rollpanna's heart. She also wields super strength and flight capabilities, though she prefers to avoid confrontation unless necessary.

Gentleness and empathy define Melonpanna's personality. She feels profound devotion to her older sister, Rollpanna, whose creation she actively requested. During Rollpanna's baking, Melonpanna contributed her own melon juice to the dough, hoping to foster a close sibling bond. Baikinman sabotaged the process by adding a "baikin plant" (evil flower), resulting in Rollpanna developing dual hearts—one good and one evil. This event forged Melonpanna's protective role; her presence or melon juice can counteract Rollpanna's evil impulses triggered by encounters with Anpanman or other stressors. Melonpanna also acts as a caregiver to Creampanda, treating him as a younger sibling despite their lack of biological relation.

Her narrative typically involves resolving conflicts through emotional connection rather than force. She frequently intervenes to calm Rollpanna when the latter's evil heart dominates, using their sibling bond to restore her goodness. Melonpanna occasionally requires rescue by Anpanman or others when facing threats beyond her abilities, such as encounters with Houtaiman who immobilizes her with bandages.

In broader media, including the film "Soreike! Anpanman: Yomigaere Bananajima," Melonpanna appears as part of Anpanman's core team, assisting in collective efforts to overcome adversaries. Her background remains consistent across all appearances, emphasizing her origins, familial relationships, and pacifistic abilities.