Japanese indie rock band Moools (the name is derived from the Japanese pronunciation of the word "morse") formed in 1997 and are best-known for their loose, improvisational live style and their close connection with K Records and the American Northwest indie music scene. Guitarist and vocalist Yasuaki Sakai met drummer Masato Uchino and bassist Mitsuhiro Ariizumi while at college in Tokyo, and upon starting the band, formed a relationship with Tokyo's Rebel Beat Factory label, partly due to the fact that it was the then-current Japanese home of Modest Mouse, for whom they became a regular support band.
The band had their first full immersion in the Northwest scene when they were invited to act as backing musicians for the Japanese band Loud Machine at the Yo Yo a Go Go Festival in Olympia, WA in 1999, the same year they released their debut album, Hikari Fiber. Sophomore effort Magic 2000 followed in 2000, after which Moools moved to the label Poet Portraits, where they released two more mini-albums in 2002, as well as keeping up their usual high pace of compilation album contributions.
Moools became frequent collaborators with K Records founder Calvin Johnson, with whom they became regular touring mates, and they served as Phil Elvrum's backing band during the Microphones' 2003 Japan tour, with a live album of these shows following on new label 7 e.p. Their first foray into overseas recording came with 2005's Dub Narcotic Session EP and a live album, again recorded with Phil Elvrum. Between 2006's Motif Gaeshi and 2010's Weather Sketch Modified, Moools continued to work with other artists, releasing the remix EP Tournament, which included contributions from the Tenniscoats, Calvin Johnson, and Shugo Tokumaru, as well as overseeing the re-release of their Rebel Beat Factory and Poet Portraits work over the course of two compilation albums. Members of the band have also performed regularly in other projects, with Sakai and Ariizumi playing in the band Kabaddi Kabaddi Kabaddi Kabaddi, and Uchino playing with Swarms Arm and Toddle (along with ex-Number Girl guitarist Hisako Tabuchi).