Up the duff
Pregnant.
Person 1"Why isn't Trish drinking?"
Person 2"She's up the duff."
Where it's from
Duff is an old word for a boiled pudding, as in plum duff. Recorded in Australia from the 1940s.

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While you're here
Extremely thirsty. Also used for weather that has not seen rain in months.
Going at something with great enthusiasm. A masturbation joke.
Asking a woman to show you her genitals. Probably not the smoothest way to do it.
It's your problem or project; I'm only helping. Don't blame me.
Leaving right now, in a hurry.
He will have sex with anyone or anything.