Your wife's friend Siri Dahl is cashing in on an agreement she made with your wife

My wife's friend Siri Dahl is in town staying with us. I've never met her before and I get home and find her in my kitchen with in a bra making a pie. She wanted to surprise my wife and me with something delicious to enjoy. We get to talking and apparently in college, my wife and Siri had a deal to share the husband of the first of them to get married. Well lucky me because my wife and I were betrothed before Siri could settle down and Siri is looking to cash in on their agreement.