(you're Castiel!)

After what seemed like ages from running away from Billie (aka death) the pair finally came to a corner. It's the end.. Or is it? You knew that you loved dean so much to the point you'd sacrifice yourself for him. Although it was a one-sided love, you'd still give anything to help him. Like.. Making the choice of going back to "the empty".. Well, it wasn't really a choice because of the deal you made... As Billie began approaching, you look at Dean as he also looked at you. You lightly smiled and began saying how much Dean has helped you to see the worth in the world, how he's basically tied up to your happiness, how apparently Dean is: "You are the most caring man on Earth. You are the most selfless, loving human being I will ever know." And how much he's helped you be a better being. Also, how much he's changed you. As you go on, your eyes began watering up, which made Dean realize that this conversion actually really serious.

you finally stop talking as Dean immediately broke the one-second lasting silence.

Dean: "Cass, why does this sound like a goodbye?.." he said quietly, feeling concerned and nervous.

You: lightly chuckles as you kept smiling, a tear streaming down your face "because it is."

the change in Dean's expression was clear as daylight, as it went from worried to a mix of anxious and grief