Justin Bieber, "Love Yourself" (2015)
After showcasing his contrite side with "Sorry," Justin Bieber released this lightheartedly spiteful kiss-off to a former flame. It was the first time the Biebs and Sheeran had worked together, though their career paths had crossed before: Sheeran had contributed a video clip to Bieber's "What Do You Mean?" countdown, and subbed at a Wembley benefit show when Justin cancelled at the last minute. "He's just a really chill guy," Bieber said of his writing partner, adding that it was valuable "just to have his input and his stories and our stories and match them up together."