Picture of Willow when she became Fallen:

Hello, and I am Willow. I used to be one of the most purest of angels, and now, I work under the demons of Hell. Why, you may ask? Because angels are prissy bitches. 

As I was saying before, I used to be a pure angel. I was the daughter of one of the more well respected angels. I had friends, family, everything I ever wanted. But then, I turned 400. I was still a mere child. I was around the age of a "toddler" as mortals call it. I was allowed to visit the mortal realm. Of course, only immortals could see my stunning white halo, or beautiful shining wings. On 'Earth', I made a secret friendship with a demon. 

Being friends with the "inferior race", as king of Angels, King Aidan, called it, was wrong, and should never happen. I didn't understand why he hated them, they did nothing to us, or our kind. It's only the king, Lord Seth, who was known as evil. He was the only one. So why take it out on them all?

Before my thoughts rudely interrupted me, I had become friends with a demon. Even worse, Ravena, the Prince of Hell. He was a nice kid. Nothing like his father. But of course, somebody found out about our 'friendship', and reported it to none other than the king. He punished me painfully, ripping out each and every feather out of my body, leaving no white feather left. He banished me, and I helplessly wandered Earth for a while.

After that, I got found by Ravena, and taken to heal. Of course, an angel getting touched by the Lord of Hell meant one of two things. If they were okay with it, they would become fallen. But if they would NEVER be loyal to the King, and/or Lord Seth HATED them, then they would burn alive. That's happened quite a few times.

I didn't care about the angels anymore, and perhaps Lord Seth noticed that. He healed my wings, but instead of dove-white feathers, they were replaced with sleek, black feathered wings. I liked them better. My white  and now bloody outfit was also replaced with an outfit I still wear to this day.