Chihiro Onitsuka (鬼束 ちひろ, Onitsuka Chihiro) (born October 30, 1980) is a Japanese singer-songwriter. In 2000, Onitsuka released her debut single "Shine" and gained a recognition with its follow-up "Gekkou" which became a hit. Insomnia, her first studio album released in following year topped the Japanese Oricon chart and sold more than a million copies.