placing a section of PVC pipe in someone's butt, then sticking barbed wire into the butt via PVC pipe. initially, the barbed wire is contained within the PVC pipe. you then remove the PVC pipe, leaving the butt free to clamp down around the barbed wire. many people use this as stimulation before, during, or after sex.
Angela was extra horny Tuesday night, so she let me cactus punch her. Incredible!
The act of shaving your nether regions too far in advance of engaging in sexual intercourse; this results in a 5 o'clock shadow causing the sexual partner to feel as if they are being punched in the genitals by a cactus.
I shaved my junk on Wednesday and then hooked up with a chick on Friday. I totally cactus punched her.