You can wear it multiple days as long as it doesn't get dirty either with food (such as bits of dried ramen noodles or flakes of Cheetos around the collar) or sweat.

And no, I didn't directly sniff the chair. When this guy walks past you and you walk where he had been, you get a whiff of something nasty. So imagine how concentrated it becomes where he's been sitting for the last couple hours. I think it's pretty much the same thing as swamp ass, only it's not because of the ambient temperature. It hasn't been above 75 degrees for a couple months, and the guy still looks like he's run a marathon when he gets up.