The role of a large-scale villain like Otomono Kuronushi, who is plotting to take over the entire country, is called Kunikuzushi.

As shown in the video clip, as soon as Sekibe himself has revealed his true character, threads holding the top layer of his costume at the shoulders are pulled, and the costume on the upper half of his body flips down in front and back to change the costume instantly. This mechanism is called Bukkaeri. The sekimori costume changes to Sokutai (ceremonial court dress) worn by court nobles. Also, when he takes off his hood simultaneously with the Bukkaeri, his hair style also changes to the Oji style used for Kunikuzushi.
The dramatic technique of changing costumes in accordance with changes of character in roles like this, clearly shows the distinctive use of costuming in Kabuki to make individual roles obvious.