Punching someone in the anus.
I was in the middle of this awesome threesome when my buddy got a little too close to me so I ended up giving him a spider punch.
A Spider Punch is performed when receiving oral sex from a female just before you ejaculate you pull your cock out of her mouth and cum in your hand. Once you have a nice wad of cum in your hand you fling it at her like a spider web and then punch her in the nose and make her bleed. The Spider punch is typically given as payback or revenge.
Jamie spider punched Mary-Lou for giving such a shitty blow job