A simile is a figure of speech, a literary device which adds emphasis, gives visual clarity and makes a comparison between things that would not normally or literally be compared. It is distinct from metaphor which also makes a comparison because a simile uses the word "like" in its description or it may use " as...as."
In Edgar Allan Poe's poem Annabel Lee, Poe gives his poem a lyrical, but at the same time eerie quality. At the beginning, the reader may be encouraged to settle down and listen to a story about the idyllic life of Annabel Lee who has "no other thought / Than to love and be loved by me," the narrator. However, it soon becomes clear that this first person narrator is quite apparently obsessed with her to the point that he imagines that even "the winged seraphs of heaven / Coveted her and me" which means that they were jealous of the extent of his and Annabel's love for each other, an example of hyperbole which is gross over-exaggeration.
As the poem progresses, the narrator makes use of alliteration and we see it in the repeated h-sound in the fourth verse when he suggests that, "The angels, [are] not half so happy in heaven" as he and Annabel Lee have been on earth. Alliteration is often used with similes (for example, as busy as a bee) and the above statement is the closest to a simile as possible with the narrator saying that the angels are not as happy as he and Annabel Lee are. Angels' happiness could not normally be compared to earthly happiness and angels are not comparable to humans. "As happy as a lark" or "as happy as Larry" are common similes and "Larry's" origin is mostly unknown and only presumed.