You always thought you had problems with being insensitive down there, however, it would appear you just jerked off too much and lost sensitivity, 2 months in chastity fixed that.
You never expected your house maid would find your key and then blackmail you to stay her little toy when she caught you wearing your cage and took some photos. If you fired her, she would just release the embarrassing photos.
It's been 25 days of being locked up, at the start you swore you'd never suck dick, but a strap on doesn't count, right? Now that its the only way to earn release, you hope it still works.