Many years ago I was on a nearly full non-stop flight from L.A. to Sydney Australia.
I sat just behind a clearly retarded man in his mid twenties traveling with his parents.
The stink was unbearable. As we were located near the galley the stewardess put on a very strong pot of coffee in an attempt to mask the hideously repellent odor.
Today I laugh about it but man oh man it was bad.
Yeah yeah I know we can’t say “retarded” any more...but he was.
I was once seated next to a very large woman, wearing a tank top, who clearly hadn’t showered in a while. It was Honolulu to LA, so only 5 hours (IIRC, but it was over 20 years ago), but it was unbearable. I don’t know how you made it that far without being sick!