Australian slang.

Pissing in a person's pocket means to insincerely attempt to convince a person that you're doing them a favour, when you actually have only your own interests (generally either making a profit or ingratiating oneself) at heart.

i.e. You are pissing in a person's pocket, and trying to convince them that you're doing them a favour by warming their pocket. But realisticly all you're doing is soaking their pants in urine.
"That salesman was a complete dickhead. Constantly pissing in my pocket, trying to tell me how much I needed (insert product here)."
by Dave_3141592 November 15, 2004
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