Welcome back DragonLily to Device Bondage. In the 2 years DragonLily was off she went out and became a certified Cougar. We are glad to have her back.
So lets just get to it, shall we? The sybian is the most strenuous hitachi on the planet. It will rip and rip ejaculation after climax out of you. If you are bound and impaled on one you have no hope of not cumming. But cumming is not your real problem - not jizzing over and over and over what you need to be worrying about. The Sybian will destroy you. It will stimulate and make you spunk until you either pass out or slip into slave-space so deep you're gone to the world anyway.
It's hot for us to watch someone vibrated to near hysteria. But for the victim it commences as pure heaven that slips slowly into a private hell you can not imagine, as you are made to cum and jizz with no hope of stopping it.