I will take your bag's seat

A rucksack sitting on a train seat between two people

If you have your bag sitting on a seat it is a certainty that I'm going to try and sit there. I seek out those seats πŸ˜‚. I will even wake you up from your pretend slumber and ask you to move your bag so I can sit there. If you are man spreading along with the bag seating then it's even more likely I'm going to choose you. I do it to make you uncomfortable. And because I want to sit and you didn't pay extra to take up two seats on the Tube.