Espionage in the Resistance War: I Have a Background Editor!

Time: Autumn 1937. The Battle of Shanghai is over, and the city has fallen. The protagonist, Liu Yunchuan, is a notorious playboy in Shanghai, a secret agent for the Shanghai station of the Military Statistics Bureau, and later joins the Chinese Communist underground. He is also a transmigrator with a built-in background editor... With this cheat at his disposal, senior Japanese officials all become his backers. Who would dare cross him with connections like these? What intelligence could he possibly fail to get?