Fronted by vocalist Izumi Sakai, ZARD is one of the best-selling acts in Japanese history. Before launching the project in 1991, Sakai worked as a professional model under her birth name, Sachiko Kamachi. Encouraged by music industry executive Daikō Nagato to mount a career as a pop artist, she released the debut single "The Good-bye My Loneliness," which debuted at Number 9 on the Oricon charts and doubled as the title track of ZARD's 1991 debut album. In the wake of the album's success, ZARD became a five-piece band featuring Fumihito Machida, Hiroyasu Hoshi, Kōsuke Michikura, and Kimitaka Ikezawa. This lineup appeared on ZARD's second album, Mō Sagasanai, which was released in 1992 and featured a pair of Top 40 hits. By 1993, though, her bandmates had left the group and Sakai was once again the sole member of ZARD. For the remainder of Sakai's life, ZARD was essentially her solo project. 1993's Yureru Omoi peaked at Number 1 and became the year's best-selling release. 1994's Oh My Love, 1995's Forever You, 1996's Today Is Another Day, and 1999's Eien all reached Number 1, too, which each release selling more than one million copies. ZARD enjoyed similar success on the Oricon Singles chart, where 12 songs — including "Makenaide," "Yureru Omoi," "My Friend," and "Unmei no Roulette Mawashite" — became chart-topping hits during the 1990s. ZARD continued to release successful pop/rock records during the early 2000s, with 2001's Toki no Tsubasa reaching Number 1 and two additional records, Tomatteita Tokei ga Ima Ugokidashita (2004) and Kimi to no Distance (2005), both charting within the Top 3. However, a diagnosis of cervical cancer sent Izumi Sakai to the hospital in 2006, and she never fully recovered from the disease. She died the following year on May 27, 2007, at 40 years old.