Rubberdolls who've had their mouths lined with latex face a painful retraining period. The rubber resists every movement of their tongue and lips, while deadening all feeling.
It takes weeks of exercises for recently upgraded rubberdoll to perform orally at a minimally acceptable level.
Blinded and encased, head to toe. Immobilized completely. All you can do is take it, take the plastic cock that is slowly shoved into your mouth. It’s not even a human hand doing it. You know it’s a machine. There is not even anyone watching you. You are being used by a machine. Trained really. It slowly pushes in, then pulls out, then repeats that over and over. Then it speeds up a bit, then a bit more, then slows down again. And then it pushes in a little deeper. The machine will not stop until all of it is buried in your throat.