Great ideas! Or...maybe the spikes themselves (and/or the inside walls of the cage) are lined with itching powder, instead of his cock. That way there's even more incentive for him not to move around and cause his cock to rub against the itching powder coated surfaces. It would have to be either a silicone cage with silicone spikes, or a metal cage with spikes that are not too sharp, of course. Wouldn't want to cause injury. Not to mention if it did, that would end things pretty quickly. I'd prefer things go on for quite a while, no injuries, just plenty of desperate squirming to try to improve his predicament, when he's only making it worse in the process. *evil grin!*