Pussy torture or cunt torture is a sexual activity involving application of extreme pain or constriction to the female genitals.
This may involve directly painful activities on the female genitals, such as wax play, caning, squeezing, erotic electrostimulation, genital piercing (ex. using needles), figging (inserting ginger in vagina), using clamps, using "Pussy Spreader" device with attached clothespins (for speading labia), using speculum (for spreading vagina hole), using crotch rope, attaching weights to labia, inserting objects into vagina (ex. oversized dildo or pussy hook), inserting hand (fisting), using Sex machines, shooting water shower on her genitals, forced orgasm using vibrators or Ben Wa balls, prolonged seating on wooden horse or on sybian, etc. 
All this is done consensually in case of BDSM; the recipient may do it as she receives pleasure from it, or she may agree to it in order to provide pleasure to the sadistic dominant, or both. While the recipient is always a female, the dominant can be of any gender. Many of these practices carry significant health risks and need adequate precaution.
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