So again we're pretending the balls and stick can slip through some imaginary hole in the jeans: (1) without destroying the MC's genitals; (2) without actually tearing the jeans so they're unusable afterward; or (3) without wrecking the zipper so it never closes again. I don't know why this type of thing even gets
done in porn games. I guess it's easier to render something like this than to show the jeans unzipped with fly apart and underwear pulled down below where the dick and balls naturally sit.