The 'Penis Fish' meme centers on the Urechis unicinctus, also known as the fat innkeeper worm, which gained internet notoriety for its phallic appearance. While it has been a culinary delicacy in East Asia for centuries, the creature became a viral sensation in late 2019 after thousands of them washed up on Drakes Beach in California due to a storm. The meme is typically used for shock value, anatomical puns, or to express disbelief at the bizarre shapes found in nature. Users often pair images of the worm with captions expressing bewilderment or comparing it to various objects, making it a staple of 'cursed image' culture.