Study mentalism. Start with Bob Cassidy's Fundamentals, work through the 39 Steps in the back.
There are a number of ways this could have been done. When you see a TV show, you're not seeing any of the set up or arrangements that are done to make it happen.
I'm not a beginner in mental magic. I'm doing it professional since over a quarter-century. I also have all known books and DVDs (Corinna, Annemann, Literally everything from Osterlind, Banacheck, Haim Goldenberg, etc). I really have no idea how to make it like that! Not even with p..-s...w
Just from her reaction, it seems like there is the use of dual reality. If the effect she perceived is as it is shown, any rational person would have run away screaming to find a mob with torches and pitchforks. However, she merely reacts as if she is amused saying it is "cool."
Dual reality and Pre-Show seems right. That was also my thought, especially due to her reaction, but I wonder what they really did then. That is the question that I'm struggling with.