Mr. Bobley is a small, bird-like creature with lime-green skin, beige-tinted ram horns curling twice, and a beige beak. Dark blue bat-like wings extend from his back, granting him sustained flight. He typically makes his home within or atop Melie's massive hair.

His normal temperament is volatile and aggressive, sharply contrasting Melie's cheerfulness. He reacts harshly to perceived slights, pecking or biting during happy events, and shows combat fearlessness, confronting threats like cats. However, when Melie's curse activates, inverting her personality, his own shifts dramatically to submissive and affectionate. In this state, he actively seeks her attention despite rejection and avoids conflict.

Mr. Bobley aids Melie and her companions. During the Pompo Hills Arc, he hid when Melie was captured by the Inquisition and imprisoned in a Black Silver Cage. He later retrieved keys stealthily, enabling the escape of Melie, Seth, and Doc from their airship cell. His horned appearance resembling Seth's led to their mistaken capture by the Inquisition; they were held for three days until Seth intervened.

Despite his size, he possesses unexpected strength, capable of carrying teenagers like Melie or Seth while flying. His craftiness and stealth allow him to navigate secure areas undetected, as shown when obtaining the airship keys. His curse-linked bond with Melie causes his personality to invert whenever her Persona Switch activates, synchronizing his mental state to oppose hers. This connection defines his behavioral shifts and loyalty throughout their experiences.