Their first appearance was as the session band XI～サイ～ on January 14th, 2009. Two months later on March 11, 2009, their session band project ended and they decide to carry on as an official band. They hold their first live event on July 22, 2009 at Meguro LIVE STATION. After two months of live performances, guitarist Kiyoshi left the band at Ikebukuro CYBER. Their new guitarist Rulu fills the position on October 20, 2009. From the of 2009, they become bigger and start touring across Japan. On August 29, 2011, bassist Shun announced that he will be leaving the band and retiring from the visual kei music industry. On September 4, 2011, XI～サイ～ have officially changed the name to ラドック. On the same day, support bassist Kyouhei joins the band and becomes the official bassist a month later. On Apr