Once upon a time. Once upon a time is overrated. There is no time, not really. There only memories, hopes, despair, desire, and hate. Time and time again, hate has triggered tears and bloodshed. Has conjured wars and disloyalty. Has inspired greed. No, there is no time. Time is an illusion.
However, there is one thing, one thing that hate shies away from and takes advantage. The one thing all humans search for. Innocence. Innocence of life, of love, of naiive, of ignorance, of kindness. Angels are made of innocence. Some angels are sent down to this hateful world, to be tested. The angels are born of humanity, and tempted of all the things our souls are tempted by. The angels are supposed to forget. However, some don't forget like they're supposed to.
That's who the demons go after.
Demons are also sent to this world, to deprive all angels of their paths. They convert the angels, because an angel is the most powerful thing. When the pure angels convert, they turn into the saddest creatures alive. They turn into Dark Angels. The angels who remember try to save the angels who forgot.
Sometimes, the angels who remember must give up everything for the angel who forgets. Never has an angel who remembers gave up their purity for the angel who forgot. To give up their innocence to be a Dark Angel to save another of becoming one.
None. Besides me.