Hitomi Yamazaki serves as a stockbroker at the same brokerage firm as Tsuyoshi Aiba, performing front counter duties and assisting clients with stock transactions. She operates alongside colleagues including Aiba and Haruhiko Emoto during standard business operations, focusing on customer-facing tasks at the firm's reception or transaction counter.

Within the workplace, Yamazaki maintains strictly professional relationships with Aiba and others, demonstrating reliability through consistent presence and supportive conduct during office activities. Though uninvolved in central conflicts like stock market manipulation schemes, she fulfills her responsibilities as an integral part of the brokerage team.

Her involvement occurs exclusively during business hours at the firm. Yamazaki does not engage in Aiba's external investigations or confrontations with Lin Haifeng's organization. Her narrative presence recedes after the initial workplace setup and the triggering incident of Kurihara's suicide.

No details exist regarding her personal background, life outside the brokerage, physical traits, or character evolution during the OVA. Her role remains confined to professional functions within the financial environment.