>>8915900
Bondage with keys just out of reach as a method of taunting the victim is always great. It must be even more agonising to have the keys literally pressed up against your tits, freezing cold and irritating as hell inside your cleavage, but completely outside of your reach.
I like to imagine a would-be rescuer frantically trying to free her before the guard comes back, as she desperately moans into her gag, trying fruitlessly to get him to search the one place he would never dare look.