Aya Aizawa

A world-class idol who comes to Neuro's office to hire the detective team to figure out who murdered her managers/friends. She is their first customer when they opened their office. Her plan appears to be foiled when both Neuro and Yako incriminate her on television, though it can be interpreted that she is trying to clear her conscience by hiring them in the first place. Aya's voice not only affects humans, but it also influences plants and insects as seen in her prison conversation room. Her real name is Aya Aizawa. She is Yako's confidant when in need of advice and counselling, as they seem to get along very well, even after her arrest, as Aya believes that Yako has somewhat liberated her a bit from her guilt. She also has a rather strange relationship with the prison warden that constantly monitors her, having changed her for the weirder after singing to her (the warden has spikes growing out of her cheeks).

Source: Wikipedia