She realises

You release Amy's mind for a moment and she suddenly freezes, James' cock deep in her mouth.

"What the fuck!" she tries to say, but it comes out muffled and she quickly withdraws her face from James' cock. "What the fuck have you done to me?" she asks, pulling herself to her feet as quickly as possible. So quickly in fact that a single click of your fingers is enough to send the button of her jeans skipping across the floor and the wet fabric to fall down her legs, exposing her pantie clad arse to James.

For his part James is still sat there staring, his cock straining and dripping from Amy's saliva.