The existence of Sovereigns is a complicated story. They are Divine Beings directly born from the Light, Divine Beings who preach their words through the Light and spread forth Divinity into the world.
They chose the Second Heaven as their home simply because it has the highest concentration of Light.
The Second Heaven is a place with the highest concentration of Divine Light, so it's their favorite place to stay. But while the Sovereigns cooperate with each other, there are Divine Beings who don't.
The Deserters. They are the Sovereigns who stand against the words of the Four Elder Sovereigns. They are known as Deserters because they were banished from the Second Heaven by the Elders.
Residing in any world they can find, they fight to grow in strength and have their revenge. The Deserters spread across the Universe, and not a single trace of them could be found by the existing Order—
The Order of Light, created by the Four Elder Sovereigns!