Protein Jeans
Semen-stained jeans, usually worn by a man, though women have been known to be stained as well. Characterized by faint white splotches, and much more easily identifiable under a blacklight.
You can tell that Buzz is addicted to jerking it because of his splotchy protein jeans!
protein jeans
Denim trousers exhibiting residue of ejaculate.
Don't sit under the blacklight, man! Your protein jeans are showing!