The collar is holding his head in position by the looks of it and the face fuck is being provided by the machine? Knowing you, his body is unable to move away from the fucking stool either so not sure how he can make things easier for himself. You have to admit (please) that there's not a lot to go on in that pic. although he doesn't look as though he's dribbling so the dildo can't be all that bad. Could the other ends of the cords holding his face to the stool be connected to a more sensitive area of his anatomy so moving away causes more trouble and strife Mr Devious??