A friend of ours is a mechanic and he usually tunes our car. He's had it for the past week, coz a few things have needed doing on it and finally brought it back last night. He gave us the bill but, as it's Xmas, we didn't have quite enough money for him.
He told us that, don't worry about it, pay me the rest when you can. But I'll remind you because I know you'll forget.
But, we never forget to pay him.
Except now, we've been wracking our brains, trying to think whether we've missed something. And neither of us can come up with anything.
So, did he say this to piss us off, or because we owe him some money but he expects us to remember, rather than him telling us how much we owe?