I board the plane to Addis. I am the sixth person on the plane, but I get to my seat (12A) and it is taken.
No problem. I sit in 13A instead. A man sits next to me, he is friendly. His ticket says 13A, and makes no mention of the fact that I'm in his seat. He receives a phone call. Someone comes with the ticket for 13C, and says ‘Excuse me, you're in my seat’. But 13C is on the phone, and doesn't speak much English, and most importantly doesn't care. After all, it's just a seat on a fifty minute flight. I explain to the new man that nobody cares, and if he doesn't mind, he's best off just taking any seat somewhere else. But he insists. He calls the flight attendant.
The flight attendant asks for the ticket of the man in 13C. He produces 13A. She asks me for my ticket. I produce 12A. She asks 12A for his ticket. He produces 12J. Someone is in 12J too, and it appears that she has a very good reason for being in 12J, judging from the length of the conversation.
The flight attendant doesn't know what to do, and escalates the matter to his colleague.
Meanwhile, the man is all in on 13C. It is rightfully his! It was ordained to him, by a small stub of paper printed only an hour earlier. He allows other passengers through, apologises for being in the way, hovers over the seat, waits, expects the flight attendant to sort it out. My nonplussed friend in 13C is still on the phone.
Now there are two flight attendants trying to convince the Rightful Holder of 13C to sit somewhere else, but now all the good seats are gone. He gets mad - nothing is happening, and nobody feels much sympathy, for anyone except the flight attendants.
And then, the flight attendants solve the puzzle by asking me to move. I agree; it's just a seat on a fifty minute flight, after all. But at that exact instant, the man has stormed off down the aisle, and now sits grumpily at the back of the plane.
I sit in 13A.