Riku Aoki is a character from the anime Ghost Concert: missing Songs. She is a young woman with long, waist-length blonde hair and orange eyes, typically depicted wearing a skirt. As a member of the organization known as TERA, she operates in a world where singing has been prohibited since the year 2045, and an app named MiucS has replaced human musical expression.

In terms of personality, Riku is known for being sharp-tongued, suggesting a direct and perhaps acerbic manner of speaking. Her role within TERA is significant, as she is one of the most experienced members. She has been active in the organization for the longest period of time, second only to her colleague Setsutei. This seniority implies a deep familiarity with the supernatural threats that TERA confronts.

Riku possesses a unique and notable spiritual ability. She has the power to subjugate the ghosts and spirits around her, transforming them into plant-like forms. These subdued spirits then serve as her servants, assisting her in her duties. This ability distinguishes her approach to combat and spirit management from other members of the group. While specific details of her key relationships and personal development arc are not extensively detailed in available sources, her long tenure at TERA alongside colleagues such as Setsutei, Youtetsu, Seria Aiba, Kaede Saionji, Syuri Murayama, and Rui Ichikawa places her as a veteran figure within the team's dynamic. Her motivations are implied to be aligned with TERA's mission, which involves confronting otherworldly beings known as Great Ghosts and dealing with the phenomenon called Possession Requiem.