The definition corresponds to the word 'mood' in the sentence.
Mood refers to the feelings that a specific piece of writing arouses in the reader. These emotions are evoked by the words that the author chooses to use in his work. What the author of this sentence is trying to say is that "The Fall of the House of Usher" makes the reader feel curious and eager to know what will happen. Moreover, it is important to distinguish mood from tone, which refers to the author's attitude toward a subject.