People can be very, very strange. Take this married couple from Kalgoorlie:
Alan Robert Sloane and Rebecca Louise Sloane pleaded guilty yesterday to a string of arson attacks on homes, businesses and abandoned cars but said they had no explanation for their bizarre behaviour.
I doubt many others could come up with one either. About the only thing I can think of is that the passion had gone from the relationship and this was the only way they could, er, re-ignite it.
If that's the case you've gotta wonder what kind of romantic music they listened to on their inflammatory jaunts. There are heaps of popular songs equating fire with passion, but I think this is the most apposite.