Become an Empress and Become a Concubine

Change the wallpaper and travel through time? And he traveled through time and became an emperor? He has not been emperor for two days and is about to be killed. Who can travel through time to be in a situation like her? After escaping for a long time, he was captured by the prince and used as a maid? But my fate is up to me, I can assist the prince to seize the throne, and I can take advantage of the opportunity to become the princess.