nachtentach
When you have to greet a German who’s up all night and asleep all day. If you mess it up, they’ll probably hex you.
My teacher’s German cousin made me say 'nachtentach' or I’d be stuck with a bad grade and a cursed pencil.
I said 'hello' instead of 'nachtentach' to a German, now I have a nightmare every night.
My brother’s friend got cursed because he said 'hi' to a German who works all night.