Rythem (リズム, Rizumu) is a Japanese pop duo consisting of two female members, Yui Nītsu (新津 由衣, Nītsu Yui, born August 17, 1985) and Yukari Katō (加藤 有加利, Katō Yukari, born April 3, 1985) that was active from 2003 until 2011. They were signed to Sony Music Japan. In addition to their vocals, Yui played piano while Yuka played guitar. Rythem was known for flowing, fluid harmonies and cheerful, upbeat melodies. In 2021, they announced their comeback in a stream in their official YouTube channel.