Well if I might be so bold, I believe we can look at it along these lines. The Emperor, in his divine power, has invited over a hundred men of power and standing to enter his city to compete in battle. Obviously many will be running with hot heads and losses will be taken poorly. With this in mind, it would only seem prudent to double the guard leading to the Emperor's palace and to keep his guard close. Also that the princesses would have at least three bodyguards at all times. There are many 'lonely' power hungry men coming to the city, princess' would be prime targets. Other than that, I believe the city would be loosely run as the emperor would not to cause conflict by directly controlling those that could bring war to his realm.