Perhaps, other users can comment on other aspects of Napoleon's personality, but based on this excellent answer by u/dean84921, there is the issue of Napoleon's quoted racist attitude towards black people (Remember, this is the man who tried to reinstate slavery while in power).

Why, in 1802, did Napoleon reinstitute slavery?

I’ll let others jump in with a more detailed or accurate answer, but the memoirs of Madame de Rémusat typically portray him as somewhat unpleasant and self-absorbed, and point out that his court and courtiers had to be, for lack of a better term, needlessly fancy. Briefly flipping through to search for specific quotations, there are a few you may be interested in:

“The empress was… averse to take on anything herself, because, whether far or near, she dreaded the displeasure of her husband.”

“The viceroy himself… told his mother, in my presence, that the Emperor, jealous of the affection Eugene had won, had imposed useless and oppressive measures upon him in order to alienate the good will of the Italians.”

(In reference to attacks on Napoleon on the English press) “Those whose duty it was to bring them under his notice trembled as they did so, so terrible was his anger, whether silent or displayed in violent passion; and ill indeed was the fortune of any whose position in the household brought him in contact with the Emperor immediately after he had read the English newspapers.”

So, with the picture painted here, it’s safe to say that Napoleon would have been difficult to let your guard down around. The memoirs themselves indicate that Rémusat may have quietly opposed Napoleon, or at least been lukewarm about his political and military goals, so keep this in mind.