I recommend the ancient romance novel Chronicle of the Founding Empress Dowager to you. The female protagonist of this novel also had a son after transmigrating. However, this son not only had the ability to read minds, but he was also the previous life of the founding emperor. The male lead was the emperor, and the second male lead was the female lead's eunuch. Although there was no demon king, it was still a novel that made people unable to stop. I hope you like my recommendation, Mwah ~😗