Castiel had been staring at the same crack in the paint on the wall for 43 hours and 27 minutes. He was embarrassed and trapped in a situation that he had no reference point to get out of. Initially he was embarrassed because of the way he had reacted at dinner. He had arrived back with Dean and Sam-just the same as always, and they had welcomed him home- just the same as always. But Sam's comment about his profound bond with Dean had made him uncomfortable. So, he had left.

Dean had not mentioned what he had said to him to summon the Empty. Not when he first greeted him at the door, and not when Sam had left to get the food. Clearly Dean was not comfortable with what was said, and that made Castiel uncomfortable too, because he had upset their friendship. He did not regret telling Dean that he loved him, he was happy to finally be able to say it. But he never would have told Dean otherwise, being part of the Winchester family, being close to Dean had been enough. And it would have been enough, even now, but in the brief time he had been back, Dean could barely even look at him. And maybe that, if he was being honest with himself, was the other reason he had left the table.

He had not planned to stay in his room for 43 hours and 27 minutes, but the longer he had stayed here the harder it seemed to leave. Dean had come to the door the first night, inviting him to watch a movie with Sam and him. Truthfully, he was weary from his time in the Empty and it had not been a lie when he said that his human form needed to rest. He did not understand exactly why, but it was true. But the last thing he wanted to do was spend the evening with Dean who was clearly uncomfortable to have him there. That would hurt too much.

The next morning, Dean had tried again as did Sam. But he had said no and now, a day and a half later he was still here. Embarrassed now because he knew he was behaving like a child. Castiel, a seraph, celestial warrior, older than humanity itself, hiding in his room. Because his feeling were hurt, and he didn't know to get out of the bunker without getting them hurt more.

Perhaps he should have chosen to return to heaven instead. He thought that he could fit back into life with Sam and Dean, but he was mistaken. By doing the right thing, saving Dean, he had ruined everything else of value in his life.

As soon as the bunker got quiet, and Sam and Dean were asleep, he would leave. It would be better this way.

Sam, true to his word, was gone in less than 10 minutes. As soon as the door closed behind him, Dean went to Cas's room. Standing outside of the door with his hand raised, searching for the right words before knocking.

"Cas? You still in there?" Silence.

"Cas!?" A quick wave of panic went through Dean. Was he too late? He knocked again; a bit harder.

"Cas, c'mon man, we need to talk. Please just open the door."

After what felt like an eternity, the door opened. Dean was so relieved; he didn't notice the resignation on Cas's face.

"Dean, I should not have come. I am sorry. I'm going to leave now." Stunned, Dean didn't react in time to stop Cas from angling his way out of the door and past him. Cas never stopped, he was heading straight for the door and Dean had a bad feeling about that being the last time he'd see Cas if he didn't stop him now.

"Cas, Stop! I know I messed up but you have to at least hear me out. You can't lea…" A lump formed in Dean's throat, stopping his words briefly. "You can't leave without giving me a chance to explain."

Castiel stopped, his back to Dean. He didn't turn around; he didn't have any hope that this was going to end well, and he didn't want Dean to see how hurt he was. Even an angel has some dignity. "Go ahead."

Of all the things Dean had expected, all the things he had imagined would happen if Cas ever came back, this was not it. The internal spiraling that had been simmering for days roared back into life, faster and deeper than ever. Cas was leaving, again. He thought, well, maybe he had misunderstood what Cas had meant when he said he had loved him. Doubt clawed at his heart. What could he say to make Cas stay without making himself more vulnerable than he already had?

"You're my best friend Cas. We have to work this out. We're family."

And there it was, confirmation that he really had made a mistake in coming back. Dean would never be able to give him what he longed for the most, and while he had thought that would be ok. Now that it was reality, it was not. He had to finish this.

"You know Dean, my assignment was to return you from hell and watch over you. And that is what I have done for all of these years, long after I fell. I did my best to keep you, to keep Sam, safe and alive for as long as I could, even dying for you-more than once. My work is completed. There are no more battles to fight and you no longer need my protection. Good-bye Dean."

Never turning, not even for a quick side glance, Castiel walked away. Down the hall, up the steps, out the door. Out of Dean's life.