You're an angel. An angel that Dean has reluctantly and begrudgingly fallen in love with. He, of course, doesn't want you to know this. Especially because he doesn't trust angels very well. So, he never let's you know this. The reason he's fallen in love with you is the fact that you're so much... softer... kinder than most angels. And, maybe, just maybe, it was your pure and angelic aura that had some strange effect on his battered, tainted soul.

You, along with Castiel, defied Heaven for the Winchester boys. So, you and Cas were no longer allowed. Now, at this point in time, Lucifer was out of the cage, and the other angels were trying to get Sam and Dean to day yes to being Lucifer's and Michael's vessels.

You and a group of people Sam and Dean gathered went on a mission with the Colt to kill Lucifer. It went... all wrong... to say the least. Most members died, and the Colt proved futile in killing Lucifer. You took on Lucifer in a fight to give Cas time to get Sam and Dean out of there. Now, it's been days since Dean has seen you. The last thing he saw was Lucifer crushing you into the ground, strangling you. He could vividly remember the panicked and loud flapping sound of your invisible wings as the color drained from your face. He never even fully saw you die...