She said she had never cum from oral before. You thought you could prove her wrong so she bet you that you couldn't do it, and would be locked in chastity until you made it happen. Perhaps you were too confidant in your abilities. You thought you would
The hard plastic cage covering your privates didn't let any sense of feeling through, but for some reason you tried to still tug on it even if you knew it was a hopeless endeavor.
Its been 3 weeks since you got locked, you are not allowed any stimulation of your little clitty at all. This is what you have to resort to for orgasms now.