Truly have deviant fun with your partner with this O-ring gag and nipple clamp set
It would be fun, on its own, to slide the O-ring into your partner's mouth. The design of the ring keeps their mouth open and accessible. However, this takes things up a notch by allowing you to attach bullnose style nipple clamps. Turn the screws to apply the amount of pressure you want. The tips, coated in vinyl, keep things comfortable but effective.