Song of the Heartless

A wealthy woman named Hisako Osada is found murdered in a briefcase that was delivered to her home. Whilst the police suspect Hisako's lover to be the culprit, her daughter, An, believes someone else is behind the murder and calls on Shinjūrō to investigate. Their investigation leads them to look into an idol group Hisako managed named Yonagahime 3+1, one of its members of which, Eri, was allegedly killed in a terrorist attack. Inga uses her powers on one of Yonagahime's members, who reveals that Eri never existed and was just used by Hisako to skyrocket the band's popularity during a war. After analysing Eri's vocal data, Shinjūrō deduces the culprit to be the one behind Eri's voice, An, who killed Hisako when she told her that she wouldn't be allowed to sing in order to keep Eri's identity secret. Shinjūrō also deduces that Rinkako and police detective Izumi Koyama were the ones who started the reports on Eri, pinning the murder on someone else and continuing to restrict An from singing. Shinjūrō manages to use his connections to play An's voice all over town.