I think there was a translation problem with the word "only" that. I reformulate my idea :
In the event that your boyfriend would be invited to your home. Do you think that your parents would agree to waive your belt if, in return, your boyfriend agreed to be locked in a chastity cage by your parents.
In other words, would it be possible for your parents to accept alternation in the CB port between the two partners?
And I assumed that this case could only happen if you were at your parents' house. Because outside of your home they would necessarily refuse this possibility.