Junketsu is a Kamui Uniform worn by Satsuki.
In the Kiryuin Manor, Satsuki's father revealed the Kamui Uniform to his daughter. It was meant to be her wedding dress. Junketsu opened its eyes and gaze upon Satsuki.
Junketsu is an antagonists of the Kill la Kill anime series that was produced by Trigger. It's directed by Hiroyuki Imaishi and written by Kazuki Nakashima. The character design was done by Sushio. The series first began in October 3, 2010.
His first anime appearance was in Kill la Kill - Episode 3 "Junketsu". His character in the Japanese series was voiced by Ryoka Yuzuki.
Life Fiber Override - Kamui Junketsu (「人衣圧倒」神衣・純潔, "Jin'iattō" Kamui Junketsu)