I am pretty sure he was trying to touch her belly piercing and it stuns her as everyone was watching them dance. It was one way for him to have her get flustered and feel something coz she claimed she wasn't "feeling" anything. They looked awesome together in that episode.
Posted some pics pages back. Have a look.
Actually there was her saree in between so I'm undecided...but there's a possibility that's why she flips instantly n gives wide eyed flustered look.