The Quartet originated a long time ago, when the King at that time named his advisor’s son next king. This advisor wasn’t particularly well-liked, and that dislike spread to his son, who was really a very nice boy. Nevertheless, one day the boy, accompanied by four young men whose fathers were all noblemen who knew the King, was on his way to a concert in his honor. It was in a town neighboring the capital city, and the five of them foolishly decided to walk alone, instead of brining a guard or two and going on horseback. Well, naturally, the group was ambushed by an assassin. The four saved the boy’s life. And, although that sounds awfully heroic, what really happened was that one of the men happened to be carrying a lute and he panicked and somehow managed to accidentally bludgeon the assassin to death with it. Then the others trampled his body running back to the capital. He wasn’t a very good assassin. :/

Anywho, since everyone had been so panicky, they didn’t remember exactly how the assassin was killed, only that they had killed him, and the boy’s father and the King were impressed by the four and praised them as heroes. The King appointed them as the boy’s personal guards until coronation day. The four were given weapons and were trained to use them, and they weren’t half-bad as guards. Actually, they did a terrific job protecting the boy. So much so that when the boy was king and announced his son as heir to the throne, he appointed the four as his son’s guards. They were eventually given an official title- the Quartet- and eventually every heir was given a Quartet.