Olly took time off from his US tour to chat to Lucy in her home town, and the pair made a bet.
Lucy told Olly: “I met a boy at a festival, I’ve never met him before, I said to him, ‘If you bring ten people to my gig tomorrow, I’ll get your name tattooed on my bum.’ He brought them there. I tell you what, if you sing a song with me later on, I’ll get your name tattooed somewhere on my body.”
And after the duo headed down to the local pub to perform another one of her original tracks, it meant a trip to the tattoo parlor for Lucy.
Watch Lucy and Olly performing 'Facebook' together below!