Yuzu (ゆず) is a Japanese popular music duo. Its members are Kitagawa Yujin (北川悠仁) and Iwasawa Kouji (岩沢厚治). Both of the band members come from Yokohama in Kanagawa Prefecture.
They were discovered as popular street musicians. At first, their band name was “Lights”, but Kitagawa thought that name was too hick, so they changed the name “Yuzu”. At that time, Kitagawa was eating a Yuzu sherbet, so he named their band after it. (Incidentally, Iwasawa ate vanilla ice cream. Perhaps the band name might have been Vanilla. Sometimes Iwasawa tells this story.) The fans of Yuzu are called “Yuzukko”.