By blending the guitar-driven grandeur of symphonic metal with the glammy aesthetics of the visual kei movement, Matenrou Opera began charting hit singles on Japan's Oricon Indies Chart during the late 2000s. The group was founded by vocalist Sono and drummer yu in 2007 in Tokyo, Japan. Both musicians had previously played together in the band Jeniva, and they completed the four-piece lineup of their new group with guitarist Mika and keyboardist Karen. The latter musicians both left Matenrou Opera in 2007, with guitarist Anzi and male keyboardist Ayame filling their vacancies. Gilia, the band's debut EP, was released in May 2008 and reached Number 7 on the Oricon Indies Chart. The single "Ruri Iro de Egaku Niji" reached number 11 on the same chart, and Matenrou Opera began touring internationally in support of releases like 2009's Aomie, 2010's Abyss, 2012's Justice, and 2013's Kassai to Gekijou no Gloria. The group's busy schedule didn't suit all of its members, and Anzi left the lineup in 2016. Matenrou Opera added a new guitarist, Light Bringer's Jay, to the lineup and continued releasing new material, including the two-part album Pantheon in 2017, Human Dignity in 2019, and Chronos in 2020.