Nimblewright

Nimblewrights are constructs created to do a particular job. They are not magically required to do as anyone commands - however, they are often constructed so that the task they need to perform is fulfilling for them. For example, Kevin was created to keep a library tidy, and he loves putting books on shelves and keeping the card catalog in order.
It is possible for a powerful enough magic user to seize control of a nimblewright, which happened to Kevin. Kevin found this experience very unpleasant. The spell used to do so was likely similar to dominate humanoid.
It is illegal to own a nimblewright in Waterdeep - owning any sentient being is slavery. However, it is not illegal to have a nimblewright volunteer to help you 24 hours a day. Rumor has it that the Masked Lords are considering adopting a statute requiring that "volunteers" be paid for their labor after some number of hours.