In 2199, after humans invented "memory retrieval technology", a virus called "Forgotten River" suddenly broke out - it did not destroy the body, but eroded the memory synapses of the human cerebral cortex, causing people to gradually forget their names, love and fear while awake, and eventually turned into a walking "blank container". The only antidote is hidden in uninfected "memory fragments", and retrieving memories will accelerate the spread of the virus, creating a paradoxical crisis
