Is this John Mayer’s secret? A guitar may boost your sex appeal, a French experiment reveals. When a man asked a random woman for her phone number, she was more likely to oblige if he was carrying a guitar case than if he was empty-handed or toting a gym bag. Musical talent may signal qualities like intelligence or commitment to hard work, the researchers say. But don’t brag about your skills, warns sex therapist Dr Brandy Engler. Just invite her to hear you play in a casual setting.