Thersites is a foul-mouthed Greek servant, first to Ajax and then to Achilles, and the most determinedly unpleasant person in all of Shakespeare.
He is constitutionally incapable of saying a nice thing. Essentially a licensed fool, he casts a jaundiced eye on everything that passes by and offers venomous commentary thereon. Sarcastic, snide and sneering, Thersites is an abashed coward who punctures every high-sounding ideal he comes across and unanswerably reduces the war to an absurdity over a domestic dispute. He has no regard for anybody, Greek or Trojan, with the possible exception of himself. His mean-spiritedness encompasses the whole world, though he has a particular affection for savaging men’s obsession with sex, a subject on which Thersites is, unsurprisingly, cynical. He considers women to be whores as a matter of course.