I was flying on AC 857 last and was in seat 1K. After the meal service I wanted to sleep so put the window shades down for both windows in my pod. However the gentleman in seat 2K decided to go ahead and put the window shade closer to him back up (the one that was about 90% in my pod and 10% in his). I put it down and he puts it back up and claims he needs to work. The window shades for his own windows were both down. I politely ask him to just open one of his shades and let me put this one down but he insisted on keeping this shade open. So I called the flight director who asked him once and he replied that he wanted to keep the shade open so I was told there was nothing they could do and I could just move to a different seat. Another flight attendant passes by a few minutes after and tries to put the window shade down as the other passengers in the cabin were trying to rest but the guy kept putting the shade back up. Then another FA passes by and remarks to the second FA to not bother and just let the "passengers fight it out". Really I did not realize that the FA's role was to let passengers in J fight it out about window shades.

Anyway I ended up moving to another seat in the back to catch some shut eye and returned to my seat just prior to landing. The gentleman then proceeded to use the space in my pod (behind the seat) as his personal garbage dumping ground (used newspaper, plastic wrappers etc).

So to everyone here. What would you do if someone requests you to lower the window shade? Should flight attendants really let passengers "fight it out" amongst themselves if there is a disagreement about comfort onboard? Have you ever come across another passenger that uses someone elses onboard space as their personal garbage dumping ground?

To the passenger in seat 2K, I am sure your mother would be proud of your behavior and I hope I never have to travel with you again.