A lot of things are forgotten when you are The Last. But the first thing that The Last Dragon forgot was his name. Though he was grand and black with long golden spikes on his long winding tale, he found one bleak dawning that he no longer had a name by which to call his magnificence.
It hardly mattered of course, as he was The Last. Once people have forgotten you, they tend to stop bothering to ask for your name. There were no longer any other dragons to compare his treasure hoard to, none to marvel at his comparatively impressive jaws and claws and wings, none to hear of the daring way he defeated the knights on their hero's errands. First his own kind had forgotten him, and then so had the rest.
Most of the days he lay forgetting were spent in his cave, a grand dark structure piled high with treasure that had once been sunken or plundered or pillaged or otherwise nefariously earned. He used to like to stare for hours at the glittering of light on the coins and shields and goblets, winking stars in the inky dark. Sometimes he used to like to breath his fire breath on the metal, making it scarlet and white with heat, thinking of how it would burn the brave knight who next came to slay him, thinking of how it--unlike everything else--would not turn to ashes. But that was the second thing he forgot, the gold lust. He supposed he could hardly call himself a dragon after that went, but then there were no others to bear the title.
Though The Last Dragon had given over to sleep and immobility, to long snores and endless years, though he had long abandoned his legend to fairy tale books, he could not seem to forget the last finite pieces of his shattered self. Those pieces were things called dreams, though they had become almost inseparable from The Last Dragon's reality. There were sleeping dreams, snippets of rage roaring battles and knights with the glint of fear and awe still in their eyes, images of the perfect challenge. But then there were other things, yearnings.
The Last Dragon wanted only one thing, and it was not to be remembered, as some might have suspected. He did not want to be fearsome again, for though he was old, he was most certainly still frightening. Dragons live to be many hundreds of years old, their youth never quite spent until it is gone. (Which is what made it all the more spectacular that The Last Dragon was, indeed, the last. There was a time when no man could picture a world without dragons, so sturdy was the breed. The Last Dragon still could not picture it, as he had not left his cave since before the Second to Last and Third to Last Dragons died on glinting steel sword points.)
No, what The Last Dragon desired, more than brave new knights to frighten, more than gold and jewels, more even than to fly again, was a mate. One could suppose, in a way, that what The Last Dragon wished for was to not be The Last at all, to simply be a dragon with a mate in a cave filled with treasure. This is not so different from what The Last Knight had wanted when he came to kill The Second to Last Dragon, except that his "cave" was really more of a "castle", and his "mate" was more like a "princess". (Also, in order to accomplish his dream, he had to reduce a species by half, from a measly two to a lonely one. The Last Dragon's dream required no such violence, though he did not mind a bit of maiden capturing or knight baking when it came down to it.)
Slumbering in his dank cave which smelled of dragon breath (which smelled of wood smoke and sulfur and rust), The Last Dragon dreamed that one of the golden eggs from the Second to Last Dragon's clutch had survived the greedy human hands which had taken shining eggs and put them on cold, high shelves with no dragon mother's heat to hatch them. He dreamed that the lucky egg had turned into a hatchling and that the hatchling had grown into a dragon, as nameless and alone as he. He dreamed that the figment of a dragon searched for him, plucking the skies with her pearlescent wings.
But, of course, it was far more likely that the other dragon (if such a one existed) simple lay sleeping in a similar cavern in an opposite part of the world, forgetting how to be a dragon, and waiting for The Last Dragon who would never come. Sorrowful thoughts have a way of spinning out of control, attached to imaginings too sweet to bring real happiness, and so The Last Dragon's apathetic isolation turned slowly into torturous waiting.