"Ai no shirushi" is the 6th single released by Japanese pop duo Puffy AmiYumi. It was released on March 14, 1998. This song was written and composed by Masamune Kusano of band Spitz. Some of this song was played in the film Waterboys. They also sang a Chinese Mandarin version of it on their album The Very Best of Puffy/AmiYumi Jet Fever. Captain Funk also did a remix of it on their album An Illustrated History. There was also a special version of the song sung for the Drummania game. This song was also featured on the live action movie Lovely Complex.