"God Knows" is one of the highly popular songs in the anime series "The Melancholy of Haruhi Suzumiya." This song is sung by the character Yuki Nagato, portrayed by Aya Hirano. Here is a description of the song "God Knows" in the context of this anime:

Title: God Knows
Composer: Hidetoshi Sato
Singer: Aya Hirano (as Yuki Nagato)
Album: The Melancholy of Haruhi Suzumiya Character CD Vol. 3