I once spilt some red wine on a BA A380 (upstairs, Economy, window, bulkhead). It was on top of, and ran into, the side storage compartment.

I was embarrassed and did my best to clean it up with paper towel but it was dark, I was tired, and didn’t do the best job.

Anyhow, point being, fast forward 3 months and I found myself on the same aircraft, same seat, and you can probably guess the rest.

My red wine spill was still there to greet me inside the compartment as I opened the lid :-)