As if by primal instinct you and your neighbour had known about eachother from the first moment you met; you could sense her power and energy, and she could tell how much you longed to submit. It wasn't long before a harmless flirtation led you into her bedroom, and quicker than that she had your limbs tied off to each bedpost as she played with your cock, making it pulse and leak for hours as your tongue buried itself in her pussy until, finally, all that desperation poured out in a thick unsatisfying glob at the same moment she squeezed your head between her thighs and had the best orgasm she'd felt in years.
By the time she recovered her choice was already made but she needed to know that you wanted it too; she retrieved the cage from her dresser and showed it to you. Let your eyes run over every inch as she explained exactly how it could torment you, but also the pleasure wearing it would bring as you felt your owner's power even when she couldn't be around. Being locked for a Goddess like her was as much a privilege as a torment however and you'd need to earn it.
With your arms and legs unbound she has you kneel before her, cock still hard and begging to be touched, but she gave explicit instructions that you were not allowed to touch unless she gave permission. If you could last a week, technically free but still officially denied, she would give you the chance to become Hers and with almost no hesitation you agreed.
The week that followed was incredibly long. Your mind yearned for her, and your body was desperate to be touched, but you waited to hear from her again as she'd told you to and when Sunday finally came it felt like being at peace as she finally called you over to kneel before her again. Once she satisfied to herself that you'd been good with a quick inspection she brought out the cage again, and asked one last time if you wanted it. She ordered you not to blurt it out, but to fully consider what it would mean for your future, as you wouldn't be asked again; once locked your cock would be her permanent and exclusive property, nobody allowed to touch it ever again- not even you.
As your Goddess-to-be ordered you took that moment, but all you could see was the bliss of being allowed to ache like this, for her, forever. You looked her in the eye and could see the fear that you might actually say no turn to joy, and within moments the cage was locked.
Life wasn't easy after that. Being locked in chastity hurt a lot, especially when your cock raged against its new steel prison, but you never regretted your choice. Not really.