Proper nouns refer to specific people, places, or things. They are always capitalized. Examples include:
* People: John, Mary, President Biden
* Places: New York City, Mount Everest, Mars
* Things: Empire State Building, Mona Lisa, iPhone
"Imp" is a common noun, a general name for a small, mischievous demon or sprite.
It's like saying "cat" or "tree." While there can be specific imps with names (like "Impy" or "Little Imp"), the word "imp" itself refers to a general category, not a specific entity.