finite menu

One episode of Murder in Suburbia involves a mate-swapping club of four couples. (In this case, sex provides the opportunity but not the motive.) It occurred to me in my insomnia that, instead of drawing names from a hat, for a small fixed group it would be efficient to prepare a set of cards for the 24 permutations (or the nine derangements). Any of the participants could then veto a potential partner by removing six (or three) of the cards.