Rihanna’s “Unfaithful” (2006) is a somber R&B piano ballad that delves into the guilt and pain of a woman who is cheating on her partner. Written by Ne-Yo, the song showcases Rihanna’s emotive vocals as she confesses she’s causing hurt (“I don’t wanna be a murderer” of our love). The track’s dramatic, string-laden arrangement highlighted a more mature side of Rihanna at just 18. “Unfaithful” became a worldwide hit (Top 10 in the US), and marked her evolution from dancehall ingénue to a versatile pop/R&B artist capable of tackling serious emotional themes.