Besides, they aren't even dating yet... let the woman buy him dinner first or something, before caging him
But there's nothing to lose at that point for the MC. It's more exciting when he has things to lose right now in the present.
Seeing him caged when they're dating is like "Oh okay, yeah that's something Kim would do"
Seeing him caged now when he "still" has the option to break the relationship up and go to another girl is like "Oh crap... how is he going to explain this to anybody... he can't, he'll have to beg Kim to take it off if he wants out which comes with a price"
You could even have a scene where she forces the MC to show everyone the cage as proof. Although this might be
too humiliating even for you to write.
(Maybe it could be done with the collar instead?)
I think someone else in this thread commented on the entire deb chastity situation. I can't remember who it was. If you're reading this requote your comment you deviant.