The idiom 'What you fear most is most likely to happen' couldn't have been a more accurate depiction of Lady Shu's state of mind at this moment. She had absolutely no inkling the Emperor would make such a move to examine the Fifth Prince's homework.
Given the long roster of duties the Emperor had to handle daily, he had little time to go through their textbooks. The ones he was most concerned about were the Crown Prince and the eldest prince.
One was his first-born child, while the other was his legitimate child.
For the Fifth Prince, who was neither the eldest nor the legitimate son, the Emperor would, at most, glance through his essays once. However, with Gu Jinyu's assistance, the Fifth Prince always managed to complete his essays quite flawlessly.
Occasionally, the Emperor would summon the Fifth Prince and quiz him on some questions from his essays - all prepped in advance by Gu Jinyu.