Well, apparently Fall Out Boy fans aren't a fan of rap beefs.
Machine Gun Kelly, of course, embroiled in a beef with legend Eminem, posed onstage for an Instagram post, coming at Eminem.
What he didn't tell the crowd was that he was using them for an anti-Eminem post. When he began performed "Rap Devil", his Eminem diss track, the crowd began to boo.
Do you feel bad for Kells, or were these boos warranted?