Some of the reaches of London hold devices whose manufacture is lost to us now, but, still, have been able to maintain their function, and one such device is dubbed, the Ancient mind control altar.
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As seen in this representation, the victim or willing participant, is placed in the seat, and the Dominant subjects them to the rays from the device, that first must pass through a liquid aptly named, magical mind control fluid. A master dominant, stands about a 3 in 4 chance of capturing the mind of a full submissive in this way, and the submissive will then become the property of the person who used the mind control altar.