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WarJay77
(Troper Knight)

Alice wishes to buy an exotic, super rare and illegal pet. She knows that Bob owns one, and, seeing that he takes a cage covered with a blanket everywhere, goes to him and asks to buy it, offering an unholy amount of money for it. Bob accepts, and, after the transaction is complete, says that she "may have the contents of the cage"... which turns out to be a rock.
Edited by Linfia