This is pretty much exactly describing a dream i had as i lay sweating in troubled sleep for many hours one morning.
i really, really, really do not like deep water.
and to me, undine means "water nymph" no matter of whatever anyone else may tell you.
they are wrong! wrong i say!

this is FAR from finished, but probably never will be, as it was a bit fuzzy...
added bits would be me and the nymph as a married couple in the mid 1800's, searching for a doctor for an unkwon purpose in a modern-day residential area in some suburb.

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Undine.

The pool lay blank in the darkness of the night, the high pines around swayed in the fair wind, I proceeded down the grassy path carefully, there was something strangely familiar with the whole scene, but I could not grasp it, until...
I saw before me, the stairs, a winding, old flight of curved stairs that was worn black by the many feet that had tread on it over a time-span that I did not even bother to imagine.
On the other hand, I imagined the building, if there indeed was a building that once stood here.
I got the image in my head of a tiled floor, a clear-watered pool, much like the natural one that now lay before me, but man-made.
This was not a vision of what was gone, but of what would come, still, it did not unlock any mystery of the winding stair.
I simply walked down the worn-down steps until I reached the pool-side, in my head, the tiles lay blank, just like the water, and there was the object I had been seeking through all the clouded dream-visions of late.
A small figurine, a depiction of a slim and slender female figure, her inviting looks formed perfectly for the scenery of the clear pool, the dark waters, I could not feel anything else but the serene understanding of this little thing, it was a perfect carving of the element that has complete domination here, the sky-like lakes, sea or pools of my dreams.
I looked to the little spirit and wondered how it came to be, why it now lay abandoned on this tiled floor, while the lamps, no, stars, gleamed above.
I admired the craftsmanship for a while, the little thing almost looked alive.
The more I looked, the more I thought to see the little thing move, she shifted in my gentle grip, stretched, as if having slept for a long, long time, then gazed up to me with her beautiful, near-black eyes, giving away only a tiny hint of any colour, but a colour I could not even name.
She yawned, or meowed, it seemed to be the same manner of motion, but soundless.
I did not hold her as she began flapping lazily in my hands, what before had been legs was now a slim, shimmering tail, like a fish, she had taken the shape of a mermaid in the blink of an eye.
She pointed towards the water, the pool or the lakes?
I took a step backwards to stand up and look around, but suddenly lost footing and fell helplessly into the poll behind, shattering the mirror illusion of the calm water.
I watched the bubbles around me, more mesmerized about the array of countless little streams, bubbles and whirling than surprised that I could actually see under the water.
The little mermaid swirled around me, with every moment in the water, the inanimate little figurine seemed more and more alive.
She moved, moved some more, gracefully as she suddenly took the size of a grown woman, still slim and slender, she had no hair on her shimmering body, but her head was crowned with a single fin-like appendage, fitting her shapes perfectly.
She held out a hand for me and smiled, her full lips like a ripe sea-fruit as suddenly, we found ourselves out of the man-made pool, the light above and the fresh, polished tiles.
The surrounding now was an endless desert, sand, sand as far as I could see, it was clearly night still, for it was darker than before.
But then I realised I was not standing in the burning sand, I was hanging in what I had thought was air.
It was not air, nor was it a desert, it was a wide, almost endless underwater landscape, with no sign of the surface above, it seemed like any light that penetrated the dark water was that of moon and stars, as if they themselves were hanging on the water, down in the sea-scape.
I looked around, there was suddenly no sign of my water-nymph, the first feeling that gripped me was not despair, I had seen these murky waters before, in a dream, only this time around, I was so deep beneath.
I took a step, I would call out, but I knew, somehow, that I could not speak underwater.
The endless sand around me was soft, I was surprised that the waters were not filled with... things, either of nature or of some nightmarish horror, all this deep, all this darkness.
My next step was one that would look like a leap, caught in time and made into a slow float upwards, I took a testing swim-stroke and found myself fully capable of swimming without being bogged down by anything.
I started upwards and threw my head around to attempt spotting the slender little spirit again, hoping she had not wilfully forsaken me like the siren that leads the sailor to a watery grave.
But this was not my grave, it was far too serene for that, far too pleasant.
The surface of the endless black must have bubbled when I stepped up out of it, for to my endless surprise, as I reached the surface, my feet were still embedded in the soft sand of the bottom.
I stood up and looked around, it was as if the seas of the world flowed from my back and hair, I was a giant that had just risen from a slumber that had lasted since the olden days, and now I found my world filled with this clear, cool liquid.
The beach was not far, the pines stood still now, high and silent upon the hills around the endless water.
But how could they encase the water if it was so vast?
I saw someone sit on the shore, a slim, slender female shape.
My nymph!
I hurried to the shore, my wading steps stirred her and she looked up from weighing her head on her knees, her dark eyes were red with tears, but as she saw me, a wave of cheer seemed to fill her.
I observes her shapes as she stood up, the mermaid was gone, the same slender woman I had picked up in my hand earlier stood there, still in full size.
She waited eagerly on the shore, as if she did not dare to touch the water, until I stepped up on the rough-pebbled beach, then she threw herself around my neck, before I could react, I simply wrapped my arms around her too, so that I would not loose balance.
But I lost balance anyway, due to her kiss, her full lips pressing against mine, first as if something forced us two together, but then with a warm passion.
As I kissed back, I was already falling, back into the water, helplessly this time too.
The water soon enveloped us, but I could not feel any cold or even anything wet, it was like yet another suspension in mid-air.
The pines above, the vast endless murky darkness below, it was as if I was staring up through a completely calm water's surface, as if the life-giving liquid did not note my presence through all the basics of nature.
This time I was not alone, I could hold on to my nymph even as she seemed to appear differently again, her slender body suddenly that of what looked even more a mermaid than she was shaped when walking on land.
Puzzled, but far from repulsed, I found comfort in her arms, just as she found comfort in mine, as the sky seemed to shift above us in this endless night of nature's most perfected joining of land, sea and endlessness.

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