Noriko Oyama is a supporting character in the anime series Dai-Guard. She works as an office lady, or OL, in the Public Relations Department of the Planning Department at the 21st Century Security Guarantee Company. She is twenty-eight years old and serves as the leader of the female employees in her division. Oyama originally comes from Hiroshima, and she uses the Hiroshima dialect when speaking with her mother over the phone. Within the story, her primary role involves handling the large volume of phone calls that pour in from the public following the withdrawal of Dai-Guard from active combat. She is often seen managing communications and public relations matters for the company. Oyama's personality is not heavily explored, but she is portrayed as a capable and dependable office worker who takes her responsibilities seriously. She does not pilot the mecha or engage in combat; instead, her contributions are administrative and support-oriented. Oyama interacts primarily with her colleagues in the Public Relations division, and her relationships are grounded in everyday office dynamics. Throughout the series, she remains a steady presence in the corporate environment, handling the pressure and public scrutiny that comes with the company's involvement in giant robot operations. Her development is subtle, reflecting the broader theme of how ordinary office workers adapt to extraordinary circumstances. Aside from her communication skills and her ability to manage public relations, she does not possess any special combat or mechanical abilities.