Long, long ago there was a poor man. Since he didn't have any fuel, he went to the seashore to gather firewood. Lots of wood was carried in by the waves and tumbled around there. As he was picking up wood, he discovered that a large number of turtle eggs had been laid in the sand in the shade of a rock. Actually, he discovered that little turtles were hatching, one after another, from those eggs.
It is said that when baby turtles are born, the mother comes to greet them. She lines them up in their order of birth and leads them to the sea, not missing a single one. Remembering that story, the man looked around, and sure enough-- the mother turtle had come to the water's edge and raised her head, looking for her children. She had come to greet them, but apparently couldn't come over to them because there was a human there.
The man understood what was in the mother turtle's heart. He lined up the baby turtles and said, "Your mother's come for you. Hurry over to the water."
The babies all happily wobbled over to the water's edge, then swam off into the ocean with their mother.
A little later, the man had the firewood up on his back and was about to leave when a voice behind him said, "Thank you for what you did just now."
He looked back and saw a turtle.
"You helped my children, and I want to repay you somehow. Please get on my back. I'll take you to the Dragon Palace."
"The Dragon Palace must be far away," the man said, looking as though he didn't want to go.
"No, it's quite close. If you'll get on my back and just shut your eyes, we'll be there."
And so the man sat on the turtle's back and briefly closed his eyes. When he opened them, he saw that they really were at the Dragon Palace already.
Then the turtle said, "In a while I'll take you to the Dragon King. If he asks what you want, say you would like a bride."
The turtle then showed the man all around the Dragon Palace. When that was done, he went before the Dragon King and greeted him. And as the turtle had said, the Dragon King asked, "What would you like for a souvenir?"
"I would be pleased to receive a bride."
"Good enough. I'll give you the most lovely girl in the Dragon Palace for your bride. Please take good care of her, and live together happily."
As soon as the Dragon King had spoken, a girl of dazzling beauty was standing by the man's side.
The couple got on a pair of turtles and left the Dragon Palace. That is, they just shut their eyes and opened them, and they had arrived back at the seashore. From there the man took his bride home and they began their life together. And what a good bride she was! Not only was she beautiful, but she took good care of the man. Besides that, from then on when the man went fishing, he always caught too many fish for his basket to hold. When he went to the fields to grow rice, he had bumper crops year after year. The man was very happy. And they had three children who couldn't be matched for cuteness.
There was one strange thing, however. Once each day this wonderful wife took a bath. She would put a big tub in the middle of the room, put screens around it, and then fill it with water. But she told the man he must never watch her. Year after year, he never looked. But one time he just felt like he had to look, and so he peeped around the screen. And what do you think he saw? Swimming in the middle of the tub was a fish. What looked like a sea bream was swishing its fins and swimming around. The man was utterly shocked.
Very soon the wife came out from behind the screen and told the man, "Since you have seen my true form even though I asked you not to look, I have to say goodbye."
Then the wife turned into a fish and returned to the sea. The man and the three children did all they could to stop her, but nothing worked. This is a story of long, long ago.