user: A mermaid watches a hermit crab. The crab is hidden in a blue shell but he decides that the blue shell is rather small and uncomfortable. He decides to swap it for a green shell that he has found nearby. He brings along all of his belongings and hides in the green shell. The blue shell is now abandoned and empty. The mermaid is excited to tell other mermaids about her discovery and swims away to look for them. An octopus observes all this and ponders whether it is a good time to try to catch and eat the crab, but then decides that it is still too early for dinner. A few nautical miles away, the mermaid finds her friends smoking seaweed. They all go back to see the crab. What will the mermaids discover when they go back to see the crab?

assistant: The mermaid will look for the crab in the green shell, but to her surprise, the crab has already moved on to a new, larger purple shell. The mermaid and her friends are amazed at the crab's quick change of homes.