When this guy felt that this guy had to be tortured, she used her dick lock to punish him. The mistress felt that the best thing to do to the guy was to use her chastity humiliation to teach him a lesson. So she teased him and had him wear it then she hid the key. The mistress had pretended that they were role playing and she acted like a nun so as to have him trust her before she made him wear it.
This mistress did not want to let her boyfriend abuse her forgiving nature. That is why she chose to teach him a lesson that would hopefully serve him well. So she came with a cock lock and she made him wear it and she hid the keys. In doing so, she rendered his dick almost useless as all he could do was pee. He could only fuck with her permission as she had the key.