It is unmistakable and unforgettable, and unbelievably unpleasant: it is skunk odor. If a skunk has ever sprayed you, you know how unpleasant and hard to remove the skunk’s pungent perfume can be.The smell comes from an oily spray emitted from the skunk’s anal glands, and is composed of strong-smelling chemicals methyl and butyl thiols. This spraying is a defense mechanism.