Rythem (リズム, Rizumu) is a Japanese pop duo signed to Sony Music Japan consisting of two female members, vocalist/pianist Yui Nītsu (新津 由衣, Nītsu Yui, born August 17, 1985) and vocalist/guitarist Yukari Katō (加藤 有加利, Katō Yukari, born April 3, 1985).
[2] In May 2003, while both performers were still high school seniors, Rythem's first single, "Harmonia", was released and was used as the second ending theme song for the anime Naruto.
Rythem's second album (along with an accompanying DVD) was released in May and June 2006; it compiles their post-UTATANE works and includes full-length versions of short pieces originally performed on their weekly radio show.
In late 2006, Rythem performed a series of live concerts entitled "Acoustic Pop", before releasing another single, "Sakura Uta" (or 'song of the cherry blossoms'), in early 2007.
As well as being a tie-in for the anime series Deltora Quest (first ending theme), the single also marks the beginning of the "Third Stage" or Rythem's venture into the music arena.
[3] Yuka mentioned in an update to subscribers of her mailing list on March 11, 2011 that she has been recording demos, and it was announced that Yui will perform in a charity event, "＆SACHI vol.HOPE", on May 24, 2011 as a guest.