Not a God. A demon. He’s the Qin Dynasty official responsible for burning untold numbers of priceless ancient books.
He did this in a bid to destroy DAOist and Confucian ideas which clashed with his own rather nasty brand of Legalist domination.
Chinese culture has mourned the loss of this precious literature ever since. Worst still, LI-SI was possibly re-incarnated as Chairman MAO-ZEDONG, who went on an even worse rampage during the Cultural Revolution. May their souls rot.