Description
Nyaa-tan, a cat-like entity from Chinese astrology, strives to join the twelve Chinese Zodiac members. She lives as a freeloader with high school student Takeru Amato in Akihabara. Her appearance features medium-length light brown hair, brown-goldish eyes, distinct cat ears alongside human ears, and a thin white tail. She wears a yellow ribbon, an upside-down yellow star accessory called Hoshinoko, a collar with a golden bell, a white shirt with a sailor-style blue necktie, and a blue skirt with a large ribbon. Her outfit includes blue and white cuffed stockings and brown shoes. In battle form, she dons a white cat-themed hat with green ears and a happy face, white flower-adorned boots, and a thicker tail.

Her personality is cheerful, kind, and mischievous, often displaying playful, finicky cat-like behaviors and ending sentences with "nya." Despite her carefree nature, she shows shrewdness, resilience, and unwavering determination to join the Zodiac, even after amnesia. She enjoys playing pranks and eating curry but finds shogi boring despite a natural aptitude.

Her background reveals she once worked behind the scenes assisting Zodiac members, sharing a close bond with Chu-tan (the Rat Zodiac). Nyaa-tan sacrificed her chance to compete in the ETM 12 event to support Chu-tan, later regretting this as Chu-tan became burdened by her duties. To alleviate Chu-tan's suffering, Nyaa-tan secretly learned the Kagura Senguu—a forbidden technique affecting an Etotama (the life force of Zodiac entities). Her attempt to use it on Chu-tan backfired; Chu-tan perceived it as betrayal, replicated the technique, and shattered Nyaa-tan's Etotama. Nyaa-tan survived but lost most memories. The Zodiacs, unaware of the incident's details, protected her from Chu-tan, who now seeks to eradicate the cat clan.

Her abilities include the Cat Gun, an energy projectile shaped like a cat's paw capable of damaging structures, and the Cat Machine Gun, a spinning kick attack forceful enough to break weapons like Chu-tan's sword. She also knows the Kagura Senguu, claiming to be its first user among Etos. Her development centers on collecting twelve Sol/Lull seals through battles to earn a Zodiac position. She secured seals from opponents like Mo-tan (Ox) and Shima-tan (Horse), and won the Takamagahara Maid Café Eto Manager's Cup race—an event typically exclusive to Zodiac members—further advancing her goal.

Her symbolic exclusion from the traditional Zodiac drives her quest to define her role. She navigates conflicts, forgotten past connections, and ongoing challenges to achieve her ambition.