the online database of Japanese folkore

Hamaguri nyōbō

蛤女房
はまぐりにょうぼう

Translation: clam wife
Habitat: seaside homes
Diet: as a human

Appearance: Hamaguri nyōbō are clams that transform into human women in order to marry human men.

Interactions: Occasionally, when a fisherman catches a clam and decides to throw it back into the sea, the grateful clam decides to repay this  act of kindness by becoming the fisherman’s wife. However, this relationship can only last while the fisherman remains unaware of the hamaguri nyōbō’s true identity. If it is ever discovered, the clam must leave her husband and return to the sea forever.

Origin: Legends of animal brides marrying human men are a common theme in Japanese folklore, found in all regions of Japan. A central theme to these stories is a taboo against looking—usually at the mysterious wife’s true form, but not always. When that taboo is inevitably broken, the couple must separate permanently. Hamaguri nyōbō are a well-known example of this trope, but countless variations on this theme featuring other animals (such as cranes, foxes, frogs, and octopuses) or even monsters (such as yuki onna) can be found.

Legends: Long ago in a village by the sea lived a fisherman named Mokichi. One day Mokichi caught a clam of tremendous size. “A clam this large would sell for a small fortune,” thought Mokichi. But on closer inspection, he noticed a crack in the clam’s shell. It must have had a difficult life, and it surely had taken a long time for it to grow so large. Mokichi pitied the clam and decided to throw it back.

When Mokichi returned home, a beautiful young woman was waiting for him. “My name is Ohama. I’ve fallen in love with you. Please won’t you take me as your wife?”

Mokichi accepted Ohama as his wife and welcomed her into his home. Not only was she beautiful, her cooking was astonishingly good. In particular, her miso soup was beyond anything Mokichi had ever tasted. Mokichi asked Ohama how she was able to make such tasty soup, but she refused to tell him. What’s more, Ohama warned Mokichi that he must never see her cook, and she made him promise not to.

Mokichi kept his promise for a time, but the secret of Ohama’s cooking nagged at him. How could her miso soup be so delicious? Eventually his curiosity got the better of him. Mokichi peeked into the kitchen. What he saw shocked him: Ohama was straddling over the cooking pot and urinating into it!

That night, when Ohama served Mokichi his dinner, he was oddly silent. She encouraged him to drink his miso soup, but he refused. Then Ohama guessed what had happened.

“You saw me, didn’t you?” she asked.

Mokichi nodded.

Ohama turned around and walked out the door. She went to the seaside, knelt at the water’s edge, and cried. Slowly she changed back into her true form: she was the giant clam whose life Mokichi had spared. The clam slipped into the water and swam away, and was never seen again.

Alphabetical list of yōkai