is a Japanese visual novel developed by PrincessSoft which was released on October 7, 2004. It has been adapted into an anime television series animated by Zexcs and aired from October to December 2004 with original character designs by Aoi Nishimata. The title uses the Greek letter Φ (phi) to represent to the in the Japanese transliteration of the English word "final". The series of half-length episodes aired in Japan in October 2004 (back-to-back with W~Wish, a separate series), with the last episode ending a few months later.
