Last year I was on a FRA-CAI flight in C in row 3 of an A343.
An Egyptian woman was seated in 2A (F class) and her husband next to me in row 3 (Business).
The lady asked me if she could swap seats with me so she could sit next to her husband.
I politely mentioned to her that she was moving from First to Business class and if she was sure she wanted to do so ?
The purser also agreed to her wish and I got seat 2A in F !