Nina Mercury is a member of the Universal Guardians, an intergalactic police force, where she serves as the secretary and subordinate of Raily Claymore. She is a young woman of twenty-two with brown hair and green eyes. Her background is that of a dedicated but often overlooked officer within the organization. Her personality is defined by a combination of genuine kindness and a notable absent-mindedness. She is polite and friendly to everyone she meets, which allows her to form a close friendship with Millie later in the series. However, she is also depicted as being air-headed and extremely clumsy, a trait that manifests in a running gag where she frequently spills coffee on Raily. Her motivations are deeply tied to her romantic feelings for him, as she is in love with him, a fact of which he appears to be completely unaware. This unrequited affection is a core part of her character, driving her actions even as her own incompetence often undermines her efforts. In the story, she acts as a supporting figure, providing a link to the police force and offering assistance from the sidelines. Her key relationships include her unreciprocated love for Raily Claymore and her growing friendship with Millie. She has very little character development over the course of the series, remaining largely static in her role as the bumbling but well-meaning secretary. Her most notable ability is an uncontrolled anti-technology power that causes her to short-circuit and destroy electronic devices simply by touching them. This power is a significant hindrance in a technologically advanced universe, adding to her reputation as being incompetent. Additionally, she is noted for being the only Galactic Guardian capable of speaking the strange language of a planet that worships chickens, a unique and obscure skill.