It's easy to see only pureness when you can't see the chains, light might be a traitor, you ignore the most important thing: The Shadows...
The envy of the dark corrupted souls force everyone to stay on the floor, to never go up, to not use your wings, they wither everything... Or at least they try...
The idea of breaking the beauty, the desire to rot those who possess the virtuosity they lack, because sadness and rage empowers evil... Those are the things that hide in the shadows, the facts you cannot see, the hardships that make angel's stronger... Broken... But stronger...