Nick Jonas, Joe Jonas, Demi Lovato and Kevin Jonas perform. (Kevin Mazur/Getty Images for Live Nation)It's a warm summer night. You've managed to score a coveted ticket to the Jonas Brothers concert, where you're singing at the top of your lungs about scorching temperatures, outselling Kelly Clarkson and getting bitten by the love bug. Maybe you've bought some JoBros merch too. A tote bag. A "JB" dad hat. A graphic tee with the bros smoldering at the camera.The fangirl in you has been unleashed in a way that only a trio of brothers from New Jersey could unleash it.