Tetsu Takano first burst onto the scene as a vocalist sometime in 1991 at the age of 18 as vocalist for the band Ner-vous. In January 1992, Ner-vous's drummer left the band and Kiyoshi Moro replaced him; however, he only had the chance to play with the band for two live shows before they disbanded. In March 1992, Tetsu went to see Kiyoshii play in his new band which included bassist Hiroyuki "Marawo" Kashimoto. Tetsu, Kashimoto, and Moro became good friends for years to come.
In August 1992, Tetsu became vocalist of Malice Mizer, a visual kei rock band, alongside Mana, Közi, Yu~ki and Gaz. For the next two years they would perform live, release several demos, and have a song on an omnibus, shortly after which Gaz left and was replaced by Kami, before they were finally able to release their first full-length album, Memoire, in July 1994. Later that year the album would be released again as Memoire DX with the bonus track "Baroque", but at that point Tetsu had decided to leave the group. While the exact reason for his departure is not known, his parting words at his last show with them, on December 27, 1994, hinted at musical differences. This can arguably be verified by the sound of Tetsu's later musical endeavors, them being alternative and hard rock instead of gothic rock. While only eight Malice Mizer songs with Tetsu were recorded and released officially, nearly 10 more were written and performed by the band during that two-year period; these appear on a large number of bootlegs. Two of the songs, "Ma Cherie" and "Shi no Butou," would later be released by Malice Mizer with new vocalist Gackt; these songs feature Tetsu's original lyrics, suggesting an amicable split from the band.
Sometime in late 1994 or early 1995, Tetsu was part of the session band Forme'd Eros, providing vocals and guitar alongside Közi on bass and Yasu also on guitar and vocals. They performed only a few cover songs and the original composition, "Ima wa...". Around fall of 1995, Tetsu would team up with Yasu again to form Mega8Ball with Rikiji on bass and Nori on drums. Yasu left by the year's end and Rikiji had his friend Yoshiyuki replace him. Mega8Ball started touring again in 1996 and throughout 1997 until the release of their first album Hybrid. The band later disbanded and had its last live on December 29, 1997; Rikiji immediately joined Oblivion Dust. They released one demo tape, one album, and participated in an omnibus with Tetsu as lead vocalist. The band would later reunite without Tetsu in 2001. Rikiji has since become the only original member to stay in Mega8Ball and Tetsu has fondly referenced the band in online diary entries over the years.
Tetsu had grown tired of being in a band and not having control, so he decided to start his own solo unit. He recruited Kashimoto and Moro, friends from his Ner-vous days, as support members and entered the studio, eventually creating 20 songs. They became known as Nil in January 1998 debuting in his hometown of Tokyo. Nil's sound is self-described as "rock with punk, grunge, and funk mixed in". They toured and performed until November, when Kashimoto announced that he wanted to leave the band to pursue a traditional career. Tetsu and Moro continued on for several more lives, but eventually called it quits before the year's end. Moro would go on to start the band Mugiwara Boushi, performing as both drummer and vocalist.
In early 1998, recently bandless musicians Ryo and Den (both ex:By-Sexual) and Sakura (ex:L'Arc-en-Ciel) started a session band that evolved into a full-fledged band when Tetsu joined in the summer of 1998. In February 1999, they debuted live under the secret band name Malice en Sex, a play-on words from their former band's names being Malice Mizer, L'Arc-en-Ciel, and By-Sexual. The name Zigzo, which is a streamlined romanization of the Japanese katakana spelling of "jigsaw," was soon officially decided upon. That summer they started touring, recording, and releasing at a feverish pace. Tetsu was the primary songwriter and lyricist of the group and only a few of the other songs were written by the group as a whole. They released eight singles, two albums, and several videos within the next two years and grew to have considerable success as a group. Zigzo announced their breakup and the band's final single "Chelsea" addressed some of the concerns by the band and of the fans. The band would have The Last Scene, its series of final shows, in March 2002.