Ich ficken meine schwester.

The act of playing squash with one’s sister.

Andy: “What are you up to this evening?”
Simon: “Tonight? Ich ficken meine schwester.”
Andy: “Oh yeah, me too.”

Christmoff

Verb; meaning to have Christmas Day off work.

Andy: “I don’t have to work Christmas Day.”
Simon: “Oh, you’re off?”
Andy: “Yeah, Christmoff.”