Most of my plot ideas are more like writing exercises, but this is just a simple, fun one that I like to do when I have no idea where to go next.
Whatever song you are listening to as you are writing, include in the story. Silence counts. It doesn't have to be super specific--you can just mention that a character uses Rhapsody in Blue as their ringtone, or that Taylor Swift was playing on the radio in the car--but it is more fun if you try and get the lyrics or the meaning into the plot. It could become a couple's song, or an epic singalong, or something else.
It's just something to try and do, when you need to break some block and move on. :)