Danger*Gang was formed in September 2002 by Waka (vocals) and Hiko (guitar), with support members Ka-e (bass) and Rei (drums). In January 2003, Ka-e became a full-time band member. Their first live performance was at "akadanobaba area" on January 15, 2003. In March, they recorded their first single "Danger*Gang no theme". It was sold early at "Takadanobu area" on March 26. In April, "Danger*Gang no theme" went on sale in Indies CD shops in Tokyo. In June, Rei became a full-time member. The second press of "Danger*Gang no theme" (100 copies limitation) went on sale. In July, Danger*Gang released their first mini-album "CRASH". The "CRASH A DIVE TOUR" started in September and ended October 30, 2003. In December, 2003, Ka-e sadly left Danger*Gang. Her last live performance was on December 28 at "Urawa NARUSHISU".
In January 2005, Thera joined Danger*Gang. In July, they released their second single "Samurai", which began selling at "Urawa NARUSHISU" on July 30. A tour began soon afterwards, and ended in September at "Urawa NARUSHISU".