I still remember that the reason why the emperor wanted to die was that Ji Feiran annoyed Changhe. If the emperor doesn't kill Ji Yanran, Changhe will rebel and force the palace. The emperor's original intention was to secretly kill Fei Ran. The so-called sending the princess to the fortress is just an excuse. This can be seen from Fei Ran's release of his bird on the eve of his departure, his visit to Zi Wang (Zi Wang was absent) and what Fei Ran said to the princess. Fei ran knew that the emperor wanted to kill him, but he could not resist, so he chose to obey. Most ministers know the emperor's intention (a wonderful killing).