Leonore

Ah, distinctly I remember it was in the bleak December,
And each separate dying ember wrought its ghost upon the floor.
Eagerly I wished the morrow; - vainly I had sought to borrow
From my books surcease of sorrow - sorrow for the lost Lenore -
For the rare and radiant maiden whom the angels name Lenore -
Nameless here for evermore. 

A horrifying Terpsichore consumes the entire poem narration, revolving in some way or another always around the symbol of Leonore. It is important to realize that the alleged motivator of the poem was her in the first place, meaning that her presence encapsulates the "sorrow", the overall "bleak" feeling of the text.

And the only word there spoken was the whispered word, "Lenore?"
This I whispered, and an echo murmured back the word, "Lenore!" -
Merely this, and nothing more. 

Continuously throughout some form of repetition Poe reiterates the presence of Leonore, and in peculiar kind of rising action, he portrays a feeling of remorse and desperation.  

Then methought the air grew denser, perfumed from an unseen censer
Swung by Seraphim whose footfalls tinkled on the tufted floor.
"Wretch," I cried, "thy God hath lent thee - by these angels he hath sent thee
Respite - respite and nepenthe, from thy memories of Lenore:
Quaff, oh quaff this kind nepenthe and forget this lost Lenore!"
Quoth the Raven, "Nevermore." 

The authors state is deplorable, and the need for nepenthe symbolizes the crucial emotional weight held by the author due the loss of Leonore. Her memories, his despair.