Kurogo are persons dressed in black who help actors and manipulate stage props at Kabuki theaters.
By extension, kurogo also mean persons who do backroom work.
Kurogo are persons who appear on the stage wearing black clothes and a black hood, and there are two types of kurogo as below. Kuroko is a misuse of kurogo. Kurogo are not regard as characters in plays, so they do not play and only work as necessary. However, they are treated as characters when they appear in modern plays or comics because of their peculiar role based on a tradition of Kabuki.
Kurogo by actors
Kabuki actors wear black costumes and help other actors. They help other actors to change costumes quickly and change props. Actors' disciples or supporting players usually work as kurogo. Kurogo also manipulate a butterfly or a bird on the end of a metal stick or a stuffed animal.
Kurogo by stage hands for large props
Stage hands for large props wear black costumes and manipulate the set. They remove a rug on the stage or change settings.
Kurogo dress in other colors, and they become namigo dressed in blue when the scene is in the sea or on the shore while they become yukigo dressed in white in the scene of snow.
The word, kurogo, has the extended meaning that 'a person who is treated as 'non-existence' although he is on the stage by "tacit understanding" between audiences and actors' or 'a backroom person who is unidentified publicly.'
In Kabuki, there is a character who wears a black costume but play an active role on the stage.