You have no way of knowing

As the next scene starts you realize you still don't have any way of gauging Grace's reaction. You still can't see or hear a thing that's going on back stage. The only channel of communication you have is touch, and no one is touching you at the moment.

You try to study Cloe and Tammy's faces for any hint of what they are feeling, but Cloe is wearing a mask and Tammy is fully in character. You aren't able to get anything.

As the scene progresses with no further **** on your backside you have a thought. Phones. All of the girls have their phones backstage. Taking a photo of you in your briefs sporting an obvious erection was exactly the sort of thing you could imagine Grace doing. She could be taking your picture right now. In fact any of the girls could have taken your picture at any point. For all you know they could have sent out a text to all the girls in the audience telling them your pants are down and you have an erection with a picture to prove it. You look out at the crowd, and though you can't make out faces you can see a few phone screens.

As you follow this thought to its conclusion a hand touches your ass and gives it a squeeze. This hand could only belong to Grace or Shannon. One of your two closest female friends is squeezing your ass, and groping it. Which one though?

You are half-way through a line when a second hand touches your cock. You squeak your way through the line as the hand gives you a squeeze the a rub. You have no way of knowing if the hand on your cock belongs to the same girl as the hand on your ass, but they are both rubbing vigorously. Clearly at least one of the girls doesn't seem to mind your erection.

The hands switch placed a few times, but they don't let up for the rest of the scene. You are sure you must have missed a line or two, but you are finding it increasingly hard to focus on anything but the hands on your body. When the scene ends you are split between relief and disappointment as the hands leave. The girls are fully switching places now, with Ashley, Cloe, and Tammy returning backstage. You are sure that Ashley coming back can't be good news for you.