"Return your keys" joke
Before a friend's wedding reception, we passed out keys (blanks) to several girls and one guy. Before some toasts were made, the best man said to the guests, "Now that Jim is married and is no longer available, it is probably a good idea to have any of you girls out there with a key to his apartment to please turn it in now." Then the pre-selected girls (about thirty of them) slowly walked up and handed in their keys as they made bedroom-eyes at him and flirted a bit; some of the girls would turn in not just one key, but six or seven of them. Then the guy walked up, turned in the key, and kissed the groom on the cheek. It's probably not original, but it worked pretty well.
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