A/N: My entry for the Naruto100 'Mythical Beasts' challenge, this is based on an Indian (I think) mermaid story.
Wind Daughter:
Once upon a time, a young man, heir to a prestigious clan found that it was time to take a bride. Women from all over the world were brought before him in the hopes that they would be chosen to produce the next generation of the famed Uchiha clan. Some went more than willing, but others were forced by fathers or leaders in hopes that they would provide a valuable link to the Leaf Country, and the Uchiha clan, through marriage.
The heir to the Uchiha was bored with the procession, as woman after beautiful woman was trotted out before him. They all were the same, none of them appealed to him. (There were whispers of the prince's sexual orientation, but an heir was needed, and would be provided, like it or not.) But there was one woman that caught the eyes of the Uchiha.
She was a blond haired, green eyed beauty with the look of someone untamed and wild. She hailed from the Sand country, a true daughter of the elements. She was visiting Leaf with her two brothers, unaware of the selection going on. The Uchiha heir could not pass her by.
In order to cement the union of countries, Sasuke of Leaf wed Temari of the Sand in a grand ceremony. It was well known that neither approved of the match, but both went through with it, whether out of a sense of duty, it was never known. All that was known was that the Uchiha heir lay with his bride rarely, but within a year she had become heavy with child.
The Leaf Country rejoiced. Soon the Uchiha clan, their most prestigious and well known family, would be tied to Sand not only through marriage, but the Uchiha heir would also be niece or nephew of the Kazekage! It was something to look forward to. However, as the day of the birth drew nigh, something terrible happened in the Uchiha house.
Before they had wed, both of her brothers had sworn to Uchiha Sasuke that if he ever harmed their sister, the marriage would be annulled and she would return to the country of her birth. If this was not enough, Sasuke knew that should he ever displease his willful wife, he wouldn't need her brother's promise to take her from him. She would leave under her own power.
But as the anticipation mounted, so did the temper of the Uchiha shorten. And when the physician spoke the news of the child's gender, the man's temper snapped. He did not have control of himself until he realized that his hand had connected with his wife's cheek. There was a moment of silence as Temari glared at him, her eyes hardened and her hand raised protectively over her swollen belly. Sasuke stood over her, his hand still raised, and apology on the tip of his tongue. But before it was uttered, she had gone, leaving only a breeze behind her.
The Leaf country mourned the loss of their Uchiha bride, not only for the child she had been carrying, but also for the ties to Sand that had been lost. But it was only five years later that the red haired Kazekage and his puppet-master brother showed up on the Uchiha doorstep with a young child in their arms. She was beautiful, with a shock of reddish-brown hair and green eyes, all traits from the Sand. Her mother was nowhere to be found however, and she was never to return to her husband and her adopted country. She had returned to the Wind where she belonged.