Counterfeits.
After learning from Duncan and others about what "counterfeits" were, and that an unknown number of them had recently appeared within the City-State, even possibly engulfing large areas with their corrosion and cognitive distortion traits, Nemo Wilkins's face revealed an undisguisable horror.
Even the old ghost, whose mind flitted between clarity and confusion, sensed the terror behind this bizarre phenomenon—he kept muttering about the Queen and the Queen's Guard, displaying an anxious and restless demeanor for a long time before quieting down.
Following that, what Nemo felt was anger.
He could not accept that his long-time companion "Crow" had died in such an obscure manner—nor could he accept that a Replication of the latter was simply created and was now lying before him, which was obviously an insult to the deceased.