Anjos e Demonios
This game, takes place in a medieval setting, in which all people have two lines of magical innate power. These powers are called the side of angels and demons, and all society is based on them. (for example, a blacksmith could receive powers from the angel of the forge and fire demon.) This would help his work, so it is common for marriages to be among the same castes as this increases the chance of children having useful powers.
In our reign, the emperor recently forced the whole population to go through a rite, which took half of her powers (one side, angel or demon) and greatly increased the powers of the other side. This left our reign far more powerful than the other nations of the world.
The game began with the young characters, 14 years old, going to the rite of passage.