This is Rapex. An anti-rape device.

Rape has become endemic in South Africa, so a medical technician named Sonette Ehlers developed a product that immediately gathered national attention there. It resembles a tube, with barbs inside. The woman inserts it like a tampon, with an applicator, and any man who tries to rape the woman impales himself on the barbs and must go to an emergency room to have the Rapex removed. When critics complained that it was a medieval punishment, Ehlers replied tersely, “A medieval device for a medieval deed.”