As the sea witch explains, every step the little mermaid takes will feel as if she is walking on sharp knives, making her time on land excruciatingly painful. The mermaid has to repeatedly go to the sea to cool her feet in the water because of the pain she's in throughout the story.

Yes, in the original 1837 fairy tale by Hans Christian Andersen, the Little Mermaid's transition to humanity was far more gruesome than the Disney version. The Sea Witch warned her that although she would have the most beautiful legs of any human, every step she took would feel "as if she were treading upon sharp knives" and as if her feet were bleeding. She agreed to this excruciating pain in exchange for the chance to win the Prince's heart and gain an immortal soul. Throughout the story, she dances for the Prince despite the hidden agony, symbolizing her ultimate sacrifice and suffering for a love that remained unrequited. In Andersen's version, there is no "happily ever after" marriage; she eventually dissolves into sea foam after the Prince marries another woman.