A chess match

After a short consultation the sisters agreed to Miriam's offer.

"Very well" said Miriam. "In our experience the most effective way to defeat the DKM sisters is the arena of the mind. They are, quite simply, too stupid to know how stupid they are. Not stupid enough to engage in a contest of wits with a Theta Pi, of course... but you sisters are an unknown quantity. And they've already outsmarted you once." she said, looking pointedly as Sarah.

"If you agree, I will arrange a chess competition between one of you and one of the DKM sisters. The loser agrees to engage in intercourse with a man chosen by the winner. Do I have a volunteer?"