Postmodern Internet Trolls, Premodern Existential Crisis

Also known as "I, the Low-profile Valor"/"Starting from Black Tuesday" = What? Didn't the Wall Street stock market crash in 1929? What? The fictional Sherlock Holmes became the Mayor of London in 1891? Why? When Zheng He went to the Western Ocean, he accidentally discovered the ruins of Atlantis? I, Ai Siyi, am a man-made anomaly, codenamed [Ghost Forum]. Right now, my tasks are: Commanding postmodern internet trolls, Saving the Premodern Existential Crisis. === The protagonist is a non-human with human thinking. If you can't accept it, it's up to you. In a sense, it can barely be regarded as an FGO fan (laughs) (only borrowed some elements)