"Unfaithful" is a song by Barbadian recording artist Rihanna from her second studio album A Girl like Me (2006). Written by American singer and songwriter Ne-Yo in collaboration with its producers, Mikkel S. Eriksen and Tor Erik Hermansen, the song was released as the second single from the album on June 20, 2006 by Def Jam Recordings. "Unfaithful" is a pop ballad that contains prominent R&B characteristics, and was inspired by the works of American rock band Evanescence. Originally titled "Murderer", the song is about a woman who regrets cheating on her partner.