Following the events of Spirit of Justice, Ema has been recognized for her forensic talent, and has become the head of her own forensic investigation team. She has been assigned to investigate the murder of office worker Hiyori Otonashi, of which the victim's younger sister, Kotoha, seems to be the only suspect. Feeling sympathetic towards Kotoha's situation, Ema decides to ask Phoenix to defend her in court, and assigns her forensic team to search the crime scene for any evidence while the trial occurs.