Carny your silly we only allow one nonsense person in here, and your it.
Anyway as for a story idea.
This couple is planning a get together beach party, for an incentive to get people to go they have publicly announced that if 1500 people show up and say Hi, they will have sex in front of them.
Now of course she gets second thoughts so they curtail the advertising for the event, though a few of their friends decide with a little help from the boyfriend that they will try and get the 1500 people to come.
Now if they do or not is up to you, but I am betting that they do and sex ensues.