She was the last. She was alone.
The touch of tree bark beneath her palm was smooth and cool, feeling like glass through which hummed an ancient life energy much greater and more vast then her own. For indeed, her own life energy was growing thin. She had felt the ever-mounting change within her more acutely since having reached the dappled shade of what remained of her grandmother's realm.
It was as she caressed the satin skin of the mellorn that she had become aware of the definitive lack of presence of her fair kindred. She knew not of any brethren that lingered still upon these shores, but yet she felt sure that some must remain. The eldar would not fully deprive Middle Earth of their caring touch. Or perhaps the sense of isolation was merely because her time had finally come. She could sense its inevitable touch upon her spirit and hear its promises of an eternity spent alone.
Though, from whatever origin, the thought of her indefinite solitude did not cause her pain nor sorrow. It had been her choice and she did not, nor would she ever, regret walking its path. It had been a glorious journey, filled with such happiness she had never thought possible and standing upon the threshold of her journey's end, she did not feel any of the sadness her father had predicted those many years ago. Instead, there lay only a sense of freedom.
Freedom of which nature she found hard to comprehend beyond that of a brief and vague understanding.
It was as if she was fading from this life.
As her awareness of her thinning life energy grew, she also became aware of the lack of solidity in her body. She felt lighter then she ever had in the years before, as if only fragments of herself held her form earthbound; and when the wind blew and her long night-dark hair took flight in its breath, she felt as though her soul longed to be free and mingle with the air like dry leaves dancing in the eastern wind.
Standing now in the flickering sunshine, she closed her eyes, feeling the warmth of the sun seep into her body and give light to her insides. Would her eternity be as such? What fate awaited her here, now that she had reached the end? Opening her dark haunted eyes, she was caught unawares at the sight of her skin in the sunlight. Her fair limbs seemed to merge with the sun's glow till her entire being sparkled with iridescence and hummed with sensation. Holding one delicate hand up to light, she was filled with childish delight and wonderment to be able to see the trees beyond her through her now seemingly translucent hand.
What joy it was, to know that she was indeed passing from this life. Her fears at the impending transformation evaporated and turning her jubilant face to the canopy of leaves above her, she watched in pleasant new-found awe as the gilded light from the sun illuminated the autumn leaves in hues of reds, oranges and golds. She laughed with pure, innocent pleasure at the sight.
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Author's Notes: Yes, yes, yes. I am fully aware that I'm taking massive liberties here and sometimes blatantly ignoring what Tolkien wrote. But, I just liked the idea of it happening so gradually, she didn't even know it had happened till it was over. Kind of like getting your ears pierced as a child: you're prepared for pain and blood- and then its over before you've truly realized it had begun.
I originally had another take on the transformation of Arwen; thinking to show a traveler many years later as he passed through the forest of Galadriel where he would catch glimpses of a raven haired maiden who only appeared for the briefest of moments when the sun shone and the wind blew. In my mind if kind of reminded me of a mermaid, flowing in and out of the dappled sunlight with the wind in her hair. He would hear her as she laughed, delighted with something beyond his understanding, but to him, it would only be the slightest whisper on the wind. Thus the title-, which now means particularly nothing at all.

