Cos is named after the word COSPLAY, which means "role-playing" and animated reality show. COSPLAY is the abbreviation of English CostumePlay, and Japanese is コスプレ. It refers to the use of clothing, accessories, props and makeup to play anime works, games and ancient characters. People who play COSPLAY are generally called COSPLAYER (also called COSER). Cosplay's narrow interpretation is to imitate and dress up the characters in the virtual world, also known as role-playing. As a result, a new meaning has been derived from the internet, which is often used to describe "a person who pretends to be a certain person".