You bring this up, it's actually pretty hot.
Are there any girls who hurt their pets' balls? As long as it's not a HUGE attac to cripple them, but just holding a dogs balls and hitting them hard enough to put them in pain but not cripple them... That idea turns me on..
After all, really: If you have testicles, a woman should have the right to hurt them, whether you're dog, cat, human, or horse.