Sour cream and silicone sealant are both white substances that can be applied with a caulking gun, which makes them perfect candidates for this party game: One girl sits with the tip of a caulking gun loaded with sour cream stuck in her vagina, another with a gun loaded with silicone sealant — nobody at the party knows which gun is loaded with which. The two girls each inject a glob of their mystery substance into their vaginas. Then, two guys must perform cunnilingus on them and act like it's yummy, even though one player has the taste of caulk in his mouth. The rest of the party has to guess who got stuck with the sealant.