Find Good Songs | Music on Instagram: "The crowd understood the assignment 🔥 Song: Billie Eilish - bad guy At the 2019 Reading Festival, Billie Eilish delivered a defining moment in her career. Performing on the main stage on Saturday afternoon, she opened her set with her chart-topping hit “Bad Guy,” instantly igniting the crowd. Despite performing hours before the night’s headliner, Billie drew one of the largest audiences of the entire weekend, with fans packed tightly and singing along to e