Who sings hey and so on song in Japanese movie Water Boys 2001?

Spitz is a Japanese rock band formed in 1987 in Minato, Tokyo. Its members are frontman Masamune Kusano, guitarist Tetsuya Miwa, bassist Akihiro Tamura and drummer Satoru Katayama. The band's name comes from the German word for "point" or "peak".

Spitz is best known for their hit songs such as "Robinson" (1995), "Cherry" (1996) and "Sora mo Toberuhazu" (1997). They have released 15 studio albums, four compilation albums and 42 singles. The band has won numerous awards, including six Japan Record Awards and two MTV Video Music Awards.