Kakushi

The Kakushi are a brigade of people who work as attendants to the Demon Slayer Corps. They wear black versions of the standard Demon Slayer uniforms consisting of a gakuran jacket and hakama pants, along with a black head covering and a black and white mask to conceal their identities.

Overview
The Kakushi are a brigade responsible for different tasks, which can range from providing services to Corps members to cleaning up the battlefield after Demon attacks.

Other tasks preformed by the Kakushi include:
 * Serving as attendants of the Butterfly Mansion, where they provide aid to the manor's residents and those healing on the premises.
 * Cleaning the mess often left behind after a large battle.
 * Sewing and repairing the uniforms Demon Slayers wear.
 * Transporting people to and from the Swordsmith Village.

In some cases, Kakushi are Demon Slayers who have been injured and retire from being Demon Slayers. There are also individuals who failed to pass the Final Selection examination but become Kakushi in order to still be of use to the Demon Slayer Corps.

Trivia

 * It has been revealed in a Sengoku rumor that the Kakushi were formed in the Sengoku era. After the traitor Michikatsu killed the then-acting leader of the Demon Slayer Corps and took his head to Muzan Kibutsuji, more effort was put into hiding the master's residence. That was also the time when the Kakushi were first formed.