"Kōfukuron" is the debut single by Japanese singer Ringo Sheena and it was released on May 27, 1998 by Toshiba EMI, East World. Since Sheena suddenly gained popularity, it was decided that this single was resold as a 12 cm single. New edition, including the new song, was re-released with the fourth single "Honnō" on October 27, 1999. The 1999 edition was certified gold by the RIAJ for 200,000 copies shipped to stores.

Yumiko Shiina , known by her stage name Ringo Sheena , is a Japanese singer, songwriter and musician. She is also the founder and lead vocalist of the band Tokyo Jihen.