The cat may pinch the nose of the dumpling out of curiosity or out of play. Cats like to use their mouths and paws to explore things around them, so they may use their mouths to pick up an object, such as a dumpling nose, to explore its shape, texture, and smell. In addition, cats also pinch things when playing. Cats will pinch soft objects, such as stuffed toys, to simulate predatory behavior.
From a cat's perspective, pinching a dumpling's nose may be as fun as playing. If your cat often pinches its nose or other objects, you can provide it with some safe and healthy toys so that it can satisfy its curiosity and predatory desires in a healthy way.