It would be a site where folks could start auctions based on stuff they want from other folks. So Bob wants Janes jumper. He goes onto the site, creates an auction with an initial offer of $5. Jane is informed that Bob wants to buy her jumper. She turns down the offer. Bob raises his offer to $10. She declines the offer. Then Cane joins the auction and makes an offer for $15. Jane refuses that too.
One see where this is going. The point is that Jane cannot shutdown the auction and anyone can make a bid. The trajectory is that Jane will reach a point where she is forced to make a moral choice (much like in the film). Everyone has their price, even Jane in this case.
It is easy enough to imagine what besides jumpers will be placed on the site. It is an highly immoral idea and something akin to cyber mobbing or AI fake porn. So does the site exist already? Asking for a friend.