The Napoleon Dwarf cat is a very cute pet cat. Their characteristics when they grow up include:

1. Short Legs: This is the most conspicuous feature of the Napoleon Dwarf cat, and all of their limbs are shorter than those of a normal cat.

2. Large Eyes: The Napoleon Dwarf cat's large eyes are another attractive feature of theirs, which makes them look innocent and cute.

3. Sturdy body: Despite their short legs, Napoleon Dwarf Cats have a sturdy body.

4. Variety of coat colors: their coat colors can have many variations, including solid colors, spots, stripes, and more.

5. Friendly Personality: Napoleon Dwarf cats are known for their friendly and social nature, and they greatly enjoy human company. Each cat will have a different personality, which is still to be seen on an individual basis.