It has some similarities with duets (which I also love), but there is a greater feeling of elemental and temporal displacement between the hero and heroine: elemental because one is singing whereas the other is speaking (in contrast to duets where both are singing), and temporal because the speaker is not responding to a live performance but to a recording of the singer (in contrast to duets where both singers are responding to each other in real-time). It is thus perfectly suited to themes of separation, regret and imagined possibilities that did not become real.
Do you like duets?