Wum, Wom, Warm

Was just out in the brisk breeze to pay a couple of bills (Health Insurance and Water) at the Seven-Eleven. (When they say convenience store here, they mean it!) I was waiting at a crosswalk for the light to change, and a couple was standing slightly behind me. She said something to him I didn't catch and he answered, "wum." She said emphatically, "wom." They said the same words to each other, with the lady clearly enunciating each time, "wom" to which he answered, "wum." The light changed, as we started across, I turned to the lady and said clearly, "warm." We all laughed heartily.