The Sand Trap

You rub sandpaper on your condom so it is grippier, and you stick it inside a girl.

Guy 1: “Hey how was last night?”
Guy 2: “It was great. I used the sand trap on her.”
Guy 1: “Nice.”

riding the sand shark

Having sex on the beach and getting chaffing in your pussy from the sand.

Mary is walking funny from riding the sand shark.