I remind my lowly slave just how lucky he is to be locked in steel chastity by showing him all of the awful things that can happen to his cock and balls if they're left free and unsupervised. First, I crush his balls with a spiked metal ballcrusher, twisting the sharp metal spikes into his scrotum so tightly he can barely stand. Then I add electrodes to his cock, cranking up the electric before taking a thin, painful cane to his cock and balls, ignoring his pleas to be locked back up to continue inflicting pain on his genitals until I'm certain he's learned his lesson.