As gross as this may sound, i live with a guy who smells of a mix of stilton and stale tobacco smoke, he's depressed, never washes/changes clothes, talks, does any chores, or opens the window in his room. Everytime he opens his door to use the toilet he smokes in there too (window shut), there's a pungent odour which doesn't disperse for about an hour. Obviously he's oblivious to it, and point blankly refuses to shower.its because their sense of smell has become immune to the stench and it is now just 'normal'
In a way tho, that refreshing for me since i too will have a pungent odour eventually, and since the others in the house obviously care little about it. I've picked a good location here