The dead man in Yossarian's tent was a pest, and Yossarian didn't like him, even though he had never seen him. Having him laying around all day annoyed Yossarian so much that he had gone to the orderly room several times to complain to Sergeant Towser, who refused to admit that the dead man even existed, which, of course, he no longer did.
In Joseph Heller's 'Catch-22', the protagonist Yossarian is confronted with a dead man in his tent, which he finds quite bothersome. Although he has never seen the deceased, the mere presence of the body causes Yossarian significant irritation. This situation exemplifies the absurdity and chaos that permeate his military experience.
Yossarian's frustrations lead him to complain multiple times to Sergeant Towser at the orderly room, but Towser dismisses the existence of the dead man entirely. This interaction highlights the surreal bureaucratic nature of the military, where reality is often denied, and absurdity reigns, adding to the novel's commentary on war and madness.