ON/OFF, comprised of twin vocalists Naoya Sakamoto and Kazuya Sakamoto, are a J-pop duo from Fukuoka, Japan. Born on December 10, 1983, the brothers debuted in 2007 with their first single "Eien no Setsuna", which served as the ending theme for the dorama Fūma no Kojirō. Their unique dynamic and harmonic vocals quickly gained attention. They followed up with several impactful singles, including "Two Heartbeats and a Red Sin" and "Rinne - Rondo", both of which were used as openings for the anime series Vampire Knight and its sequel. Their debut album, Legend Of Twins Ⅰ-Futago Densetsu- , was released on April 22, 2009 and featured several tracks from their earlier singles. In 2010, ON/OFF's single "Butterfly" was used as the second ending theme for the anime series Durarara. They also contributed to the soundtrack of the anime Beelzebub with their song "Hajimaru no wa, Sayonara". The duo continued to release music and performed extensively until their retirement from the entertainment industry on January 3, 2015. Their discography includes singles like "Hanagakari-", which was released as early as March 4th, 2009, showcasing the brothers' versatility and consistent output of musical content.
