You're an angel of the Lord. Or, at least, you used to be. You haven't really been that for a while. Of course, you're still an angel. But a fallen angel now. This is because you betrayed Heaven to help the Winchester boys put Lucifer back in the box. Just like Castiel did.

The whole reason you did this is because you, an angel, fell completely in love with the boy with the demon blood. Sam Winchester. You couldn't help but want to protect him when you first met him. He was so broken and lost. Addicted to the blood. He just needed someone. You became that someone, and because of that, Sam fell in love with a literal angel.

Years have passed since then. So much has happened, and the world seems to continuously tear the Winchester boys down. But, recently, it seems you've been torn down. Megatron manipulated Cas, and because of that. Heaven fell. The angels did. And, you happened to be unlucky enough to be in Heaven during the fall. The last thing you remembered was the fire... the falling... and the colliding.

You've been missing for months. Sam and Dean assumed you were one of the many angels that died during the fall. This, of course, tore Sam apart, but he didn't let it show. Sam, recently had just quit the trials to shut Hell because they almost killed him. Whilst on his deathbed, Dean tricked him into saying yes to an angel possession. So, little does Sam know he's got an angel riding shotgun.

One day in the bunker, Sam is alone, doing research when he hears the bunker door open. He thinks it's Dean till he looks up and sees a very familiar figure standing before him...