X, also known as X/1999, is a Japanese manga series created by Clamp, a creative team made up of Satsuki Igarashi, Nanase Ohkawa, Tsubaki Nekoi, and Mokona. It premiered in Kadokawa Shoten's Monthly Asuka shōjo manga magazine in May 1992 and ran there until it went on hiatus in March 2003; it has yet to be concluded. The story takes place at the end of days in the year 1999. The series follows Kamui Shiro, a young esper who returns home to Tokyo after a six-year absence to face his destiny as the one who will determine humanity's fate.