The Japanese visual kei band Matenrou Opera was formed in October 2006 by Sono, former vocalist of the short-lived Jeniva. Shortly thereafter he was joined by guitarist Mika, bassist You, keyboardist Karen, and another former member of Jeniva, drummer Yuu. They spent six months writing, rehearsing, and designing costumes before playing their first gig at the tiny Urawa Narciss club just north of Tokyo, and released their debut single "Alkaloid Showcase." The band's name means "Skyscraper Opera" and was intended to represent a fusion of the classical and the modern. Inspired equally by genre giants X Japan and Luna Sea, and classic European heavy metal acts like Helloween and Yngwie Malmsteen, their powerful, driving, melodic sound and technical proficiency earned them fans from the outset. They attracted additional attention not only for having a full-time keyboardist -- almost unheard of in visual kei despite the heavy use of synthesizers on the recordings -- but also that she was a woman; despite their feminine appearance, virtually all of the bands in the scene are comprised exclusively of males.
A year after they formed, however, Karen left the band, along with Mika. They were swiftly replaced by Ayame and Anzi, respectively, formerly of the bands Rydia and Sylphid. At this time, Matenrou Opera signed to Sherow Artist Society, the label owned by Kamijo, vocalist of the hugely successful Versailles. Their debut single for the label, in March 2008, was "Ruriiro de Egaku Niji" ("Lapis Lazuli Rainbow"), which hit number 11 on the Japanese indie chart, and their debut mini-album, Gilia, released two months later, went to number seven.
Thanks to Sherow Artist Society's ties to the German label CLJ, Matenrou Opera were able to see Gilia released in Europe, and also to tour there with Versailles. Their very European sound -- along with their boy band good looks -- saw them go over like a charm, especially in Germany. After returning to Japan, the band focused on recording, releasing three singles in the next year which saw them tightening up and refining their signature sound. They also released a single and played several gigs as a "secret", alter ego band named Anomie, which culminated in the June 2009 release of their debut full-length album, also called Anomie; it, too, saw release in Europe, to widespread acclaim. Later that year it was reissued with a bonus track, alongside a B-sides compilation.
Two more singles with a harder metal sound followed, after which, in May 2010, the band signed a major-label deal with the massive King Records. Their final indie show was held on August 30 at the 1,500-capacity Shibuya AX concert hall, a far cry from their humble beginnings in a tiny club just three years before. They then announced the release of a best-of album compiled from their indie recordings, and a tour to coincide with the release of their debut major-label mini-album Abyss.