Love the lubed chastity device, you might have lubed the key as well and told him he only had 3 goes at dropping it before you left him there or turned up the elecro with every drop. Maybe just slip that tray forward a bit so things in his mouth def fall into it.
I'd have left his ankles clipped to the base too, looks like they were undone by pic 6. Or was this for safety? All in all a great scene.