The act of picking up a girl at a Walmart, taking her home to have sex with her, and when you are about to cum, you pull out, put a plastic Walmart bag (must be from a Walmart) over her face, and ejaculate onto the bag that is now covering her face.
Person A: Dude, I picked up a girl at Walmart last night.

Person B: Oh, nice! Did you give her a South Carolina Windshield?

Person A: Yup! Luckily I had a Walmart bag lying around at my house to put over her head to cum on.

Person B: Good, cause everyone knows that without a Walmart bag, it's not a South Carolina Windshield.

Person A: Yeah, that's a necessity for a proper South Carolina Windshield
by SleevesAreFascistPropaganda September 20, 2018
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