Grammy winner. Multi-platinum-selling artist. Trailblazer. Still only 33, Paramore frontwoman Hayley Williams has seen it all, done it all and, as she explains, quite literally bought the t-shirts.

My Chemical Romance and Paramore are set to headline the emo-pop festival on Oct. 22 at Las Vegas Festival Grounds in in Las Vegas. Paramore will return to the stage for the first time since ...