Yuzu is a Japanese popular music duo. Its members are Kitagawa Yujin and Iwasawa Kouji. Both of the band member came from Yokohama in Kanagawa Prefecture.
They came from a popular street musician. At first, their band name was “Lights”, but Kitagawa thought that name was hick, so they changed the name “Yuzu”. At that time, Kitagawa ate a Yuzu sherbet, so he named after their band name Yuzu. (Incidentally, Iwasawa ate vanilla ice cream. Perhaps the band name might be Vanilla. Sometimes Iwasawa tells this story.) The fans of Yuzu are called “Yuzukko”.