Cora Cobb, the owner of Siegfried and Brunhilde, was very impressed by the beauty of her blue-grey cats.

This geneticist, Solveig Pfleuger, said that the breed was best defined as semi-long haired Russian Blue.

Supported by Pfleuger, Cobb wrote the breeding standard according to the Russian Blue, but with a difference: its coat length.

Russian Blue breeders from The International Cat Association (TICA), however, objected to this, and the breed standard was thus revised to describe a unique breed, resembling blue-grey cats that had been imported from Russia in the nineteenth and early twentieth centuries.

The coat is medium long on the body and longer on the tail, with lighter colored guard hairs.

The soft double coat feels fine and silky; it is gray in color and is tipped with silver.

Tufts of fur are found behind the ears and in between the toes, and the hind legs sport pantaloons.

The cat's mild-mannered state and personality may not always reflect the relatively high level of intelligence often found in the breed.

They will still enjoy the company of others within the social group but will tend to spend most of their time with said chosen person.

[8] The Nebelung is one of the animals which can be given as a Patronus in answer to the user's personality test on Pottermore.