Aya Kyogoku joined Nintendo Co., Ltd., likely as a game designer or developer. The exact year is unconfirmed, but it was presumably in the early 2000s.

Kyogoku served as the Assistant Director for "Animal Crossing: City Folk", released for the Nintendo GameCube in 2003 (Japan). This early role provided her with valuable experience in game development and project management within the Animal Crossing franchise.

Kyogoku served as an Assistant Director for "Animal Crossing: Wild World", released for the Nintendo DS in 2005. This project helped establish her within the Animal Crossing team.

Kyogoku was the Director of "Animal Crossing: City Folk" for the Wii, released in 2008. This marked her promotion to a leadership role within the Animal Crossing development team and showcased her ability to direct the creative vision of a major title.

Kyogoku took on the combined role of Producer and Director for "Animal Crossing: New Leaf" for the Nintendo 3DS, released in 2012. "New Leaf" became a critically acclaimed and commercially successful title, solidifying her reputation as a key figure in the Animal Crossing franchise.

Kyogoku was promoted to Manager of the Software Development Department at Nintendo. This promotion acknowledged her leadership abilities and broadened her responsibilities beyond a single game franchise.

Kyogoku was a Producer on "Animal Crossing: Happy Home Designer" for the Nintendo 3DS released in 2015. This spin-off title focused on interior design and demonstrated her flexibility in exploring different aspects of the Animal Crossing universe.

Kyogoku was a Producer on "Animal Crossing: New Horizons" for the Nintendo Switch, released in 2020 (announced in 2019). "New Horizons" became a global phenomenon, breaking sales records and attracting a massive player base. Her role as producer was crucial in ensuring the game's quality and success.

She became General Manager of Production Group No. 5, part of Nintendo's Entertainment Planning & Development Division. This position likely involves overseeing the development of multiple titles and guiding the overall creative direction of a team.