I believe the answer is a motif.
Both the story and the article present Nero as a bad person, but the emphasis, tone, and purpose of the two texts are very different. The story's purpose is to entertain, and its viewpoint of the events is somewhat detached. It clearly shows Nero's monster like nature, but it focuses on his egotism and coarseness. It does not include a detailed judgment of Nero's character. The article, on the other hand, focuses on Nero's character, which it strongly criticizes.
Well, despite his high achievements, Napoleon was quite a miserable person (according to his appearance and complexes). Looking on the David's painting, we can see the brave man filled with courage, who points up his finger towards the sky, showing he's ready to reach the victory whereas in the Delaroche's picture Bonaparte is portrayed like exhausted man with desperate and sleazy look. The main point is that he's not a superman, he's just a MAN, so <span>Delaroche's</span> painting is more realistic because he treats emperor as a normal human with its lacks.