Event question: On skript stop

[proper latch]

No
But you can use a in memory variable so it's never saved to file

You can scroll to the bottom of your skript config file. There it will be explained how to change to variable storage save to ignore variables that start with -, e.g. {-combat::*}. And that would be considered a memory variable

[solid rose]

yes, that method would work. alternatively, you can change the variable to be metadata on the player instead. then any time the player leaves, the info is removed