is a two-piece all-female rock band which consists of Eriko Hashimoto (guitar, vocals), Akiko Fukuoka (bass, chorus), and formerly Kumiko Takahashi (drums, chorus) who are from Tokushima Prefecture

Tokushima Prefecture

is a prefecture of Japan located on Shikoku island. The capital is the city of Tokushima.- Tokushima Prefecture and Myodo Prefecture :Long ago, Tokushima City belonged to a region known as Myōdō-gun...

 on the island of Shikoku

Shikoku

is the smallest and least populous of the four main islands of Japan, located south of Honshū and east of the island of Kyūshū. Its ancient names include Iyo-no-futana-shima , Iyo-shima , and Futana-shima...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

.

Since 2005, they have been signed to Sony Music Japan's Ki/oon Records

Ki/oon Records

is a Japanese record label, a subsidiary of Sony Music Japan.-Artists:Their artists include L'Arc-en-Ciel, Asian Kung-Fu Generation, FLOW, Home Made Kazoku, Puffy AmiYumi, Polysics, Pushim, chatmonchy, Denki Groove, The Babystars, DOES, Guitar Wolf, Miki Furukawa, Nico Touches the Walls, plingmin,...

 record label.
In 2000, Hashimoto formed Chatmonchy in the city of Tokushima, Tokushima Prefecture

Tokushima Prefecture

is a prefecture of Japan located on Shikoku island. The capital is the city of Tokushima.- Tokushima Prefecture and Myodo Prefecture :Long ago, Tokushima City belonged to a region known as Myōdō-gun...

. Having been to see her brother perform at the first concert she attended, she became keen on forming a trio.