Unfortunately for Nick, the fans wanted to see him chug!
Although, Nick managed to make slime look good!
Watch him chug (above) and get slimed (below)!
Johnny decided to show off his folksy side for the performance of his new single Wildfire, which is a totally toe-tapping tune! Along with his headscarf, he also wore some ripped jeans and a jacket with a peace sign stitched onto it.
"I have a blanket just like that!"
Ch-ch-check out John Mayer jamming out on Letterman! (below)
[Image via Twitter.]