Nyan Nyan Nyanko known as simply Nyanko for short, is one of several cute, unusual characters that are typical of the Japanese company named San-X. Nyankos are small kittens that enjoy mimicking various items, generally edible items. They can usually be seen posing from such comestibles ranging from bakery items to fast foods to fare that is typical of Japanese society (for example, okonomiyaki). Apart from that, they may also appear as everyday items, such as toys, school supplies, or household necessities. The Nyanko character lends people an idea of what sort of items can be found and are important within Japanese society. Disguising itself is a hobby of the Nyanko cat. However, it has been said that Nyankos ask not to be eaten by those who may find them. Additionally, Nyankos are often easily bored and can sometimes be seen fleeing from their place in the disguise in order to explore newer schemes of costuming. Nyan Nyan Nyanko often comes in themed sets, among these being: Nyanko Matsuri (festival), Nyanko Bakery, Nyanko Cafe, Nyanko Onsen (hot spring) and so forth.

Nyan Nyan Nyanko products come in a wide range of selections but it is reported that are not very easily found. Popularly, they can be found as small figurines or keychains accompanied in a Japanese candy box and are highly collectible. They may be won as plush prizes within prize machines in Japan's arcades. These products are of impressive detail and quality. Usually, the Nyanko cat can be removed from their costume. There are also stationary sets, pencils and children's books among other products also made with the Nyanko icon which can usually be found in Asian shops or eBay.

The term "Nyan" or "nyaa" is a Japanese onomatopoeic word for a cat's meow."Ko" is a word which in Japanese connotates with "child" or "young", so together "Nyanko" combines to be an endearing term that perfectly complements the adorable kittens who love to mimic life's little things.