Antonia Lirimonie Norfedras Papenorgas Arecroteles Cnorses Morfenoss is a 12-year-old Greek-American heiress, granddaughter of an unknown conglomerate founder. To alleviate her boredom and desperation, she founded and leads the group "Underside of Kitten Paw," alternatively known as the "Cat Ear Church." This organization venerates the Catians, especially Eris, as embodiments of physical perfection.

Physically, Antonia possesses blonde hair reaching her neck, blue eyes, and stands 1.45 meters tall, weighing 30 kilograms with recorded measurements of 50-45-50. She is rarely depicted without wearing cat ears.

Within the narrative, Antonia orchestrates the capture of Kio Kakazu and Eris in one episode, leveraging her resources to advance her group's agenda. Her maids, Sara and Maya, assist in these efforts, though their backgrounds remain largely unexplored. Following Kio's temporary transformation into a cat boy during the series' climax, Antonia develops a notable attachment to him.

Her role remains confined to her leadership of the cult and her interactions with the primary characters during specific episodic events, with no significant character development occurring across other official media like movies, OVAs, or spin-offs.