Estim pulse twitches and a vibrating finger in sissy's ass for a hands free cumshot

I've got sissy garter and stockings on, but you only get a glimplse of the real star of the show... a Lovense Ridge vibrator... vibration and a fingertip to stroke my rectum and prostate. My dick and balls are bound tight with silicone bands, and the estim pads are driving the pulsing current through my groin. The vibrator drones and diddles my ass, while I just let the estim drive. It's a surprise when I suddenly give up a cumshot.