Dual Personality Reasoner

Yunyou lives as an ordinary person in a city with a population of 12 million. Until one day, 10 million time travelers unknowingly traveled to this city, bringing huge chaos to the world. Fortunately, time-travelers have no memory of their original selves, and will die if they reveal themselves to be time-travelers. Unfortunately, Yunyou is also a time traveler, and he also needs to pretend to be different people in this city to hide his true identity.