X de Clamp Sheet Music
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.