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stage assistant dressed in black (in kabuki); stagehand; prompter
behind-the-scenes supporter; string-puller
黒子は黒い衣装で舞台を動く。
Stage assistants dressed in black move around the stage.
歌舞伎の黒子が小道具を運んだ。
A kabuki stagehand carried the props.
黒子は観客に見えないとされるが実際は舞台上でも活躍している。
Stagehands are considered invisible to the audience, but they are actually quite active on stage.