If a woman has a slave boyfriend or husband should she keep him in a cage?
In ideal circumstances a male slave is busy performing errands, chores and tasks. Often there is nothing useful for the slave to do. Given the innate immaturity of the lesser sex it is in the interests of the Mistress Owner to keep him out of trouble.
The caged slave man is harmless and comfortable.
Some dominant women use shackles and straps. Others may opt to put him in a dark, mostly empty closet. Putting the male slave in a cage seems more humane. He can move and change position. His limited freedom keeps him from being rowdy.
If there is enough light his Mistress Owner may allow her slave husband or boyfriend to read. This would give him time to study works on female superiority. It is good for slave men to understand their true nature. Of course he can be permitted to read for pleasure.
Being locked in a cage is healthy psychological reinforcement: his actions are limited by the choices of his Mistress Owner. He cannot do what she will not permit.