Back on the beat as an Electronic Investigator, Echika finds herself up against a challenging new case: a string of assaults committed against people related to the RF Model Amicus. To make matters worse, victim testimonials suggest that the perpetrator is none other than Echika's aide, Harold. As the stakes grow higher and the pair continue their investigation despite the rift forming between them, the true distinction between humans and machines becomes all too apparent. When the shocking truth about Harold comes to light, Echika struggles to make an agonizing decision...