"Bind my hands behind my back, attached to the device, of course, as that's where the ropes would originate." Zira had it planned out, already. He only needed Crowley's force of will to make it more effective, than if he willed the device to bind him, himself. "Imagine the frustration, I wouldn't be able to move without pulling on my cock, until you find time to come and free me from the ropes."