Young couple goes to the swinger club. [MF] [FFM] [MFM]

My girlfriend Sara and I were in grad school and had been dating a while. One night we were talking about fantasies and spicing up our sex life and I half-jokingly mentioned a threesome. To my surprise she fired right back and said “Sure! but who’s the other guy gonna be?” I told her that wasn’t quite what I had in mind, but we discussed it some more and determined that being with another couple might be fun. We soon ruled out anyone we knew, since we were both pretty reserved outside the bedroom and could never handle the awkwardness of asking a friend. We lived in a smaller college town, and the swinging scene we found wasn’t very vibrant for people our age. We chatted online with some couples, but never found the right situation to go all in.