If he was pressed, he'd admit to feeling that heightened awareness too. Maybe that's why he puts his head on hers and teases; no tension in that.

He sighs dramatically, squirming as she pokes at his side. "No, I have to compliment myself because you are never have a good word to say about me. I'll waste away with no support. Always have been good at taking care of myself." And as he soliloquizes, he jabs a finger into her side, all but forgetting they were in the middle of a dance.