Had a similar issue a few years ago on a BKK-CDG sector, although offending individual in that case was white.
As soon as I sat down it was obvious that there was no way that I was going to put up with 11+ hours of this rancid individual. I went back to the galley, said they had a problem and asked the purser to go and sit in my seat. When he returned he understood the problem but informed me the flight was fully booked.
My response was “no problem. I’m getting off” Much debate followed. I even offered to downgrade subject to a refund/credit.
Eventually I was offered a seat swop with an ID100 pax. Whilst he wasn’t happy with me, there was no way I was going to pay US$2K for the privilege of choking for 11 hours.