Originally formed in 2008 by sisters Be and Meana during their first year of high school, MUTANT MONSTER initially found inspiration from punk rock – particularly classic bands such as The Clash, The Sex Pistols, and The Ramones.

Later to be joined by drummer Chad (who was also a former classmate of the sisters) in 2012, the band built up a following on the back of an extensive number of live shows. They released their limited edition mini-album Follow Me in July 2009 and their first full studio album True Tone followed in 2011. Their latest album, Nekokaburi, was released in 2018.

The trio made their first overseas performance at the Japan Expo in 2016, but also found time to perform in the UK the same year with shows in Birmingham, Cardiff, Bristol, London, and Brighton. In 2017, they also graced the stage at Hyper Japan.