A/N: I felt there should have been more to Castiel and Dean's arrival in Purgatory, so here you go.
Spoilers: Up to the end of season 7.
Disclaimers: I do not own Supernatural. If I claimed that I did, someone would probably toss me into Purgatory.
Any part of Castiel's "I don't fight" ideal disappeared the millisecond he arrived in Purgatory with an unconscious Dean in tow.
Dick Roman was nowhere to be seen, but Castiel remained tense, vigilant- and not just because of the snarls of monsters in the underbrush or the seemingly all-consuming misty darkness surrounding the clearing they were in. If Dick was dead, acting as a portal to Purgatory, then it was entirely possible that he could be right there with them.
"Dean," he whispered, bending down to shake the fallen man's shoulders.
Unlike Castiel, who had landed gracefully on his feet, his friend had collapsed.
"Dean!" Castiel swallowed hard.
He had been sleeping and playing board games for too long. He had been pulled under by the insanity of Sam's burden, he realized that now. His real powers- the powerful abilities, not just simple tasks like blowing out light bulbs- were out of practice and he would need a while to regain his full strength. Here, no game of Monopoly could save them. And the monsters wouldn't care less if he was coming out of a mental break. If he didn't put himself together fast, he would be something's dinner. Soon.
He shuddered as he pictured a Leviathan stretching its maw and lunging at him, clamping its teeth around his neck—
Castiel forced down the panic in his gut. At his will, it sank down some, but the uneasiness remained.
He leaned back over Dean, shaking the man's shoulders. "Dean?" He frowned when his friend gave no reaction. "Come on, Dean. Now isn't the time for a nap." He slapped the other's check gently with the palm of his hand. "Dean. Dean!"
To Castiel's relief, Dean stirred and his eyes fluttered open.
"C-Cass?"
Castiel grinned. "Yes, Dean. I'm here."
Inhaling deeply, Dean got to his feet, with the angel's assistance.
"Where are we?" he asked.
"Purgatory." Castiel felt calmer now that the Winchester was conscious; he could see that his friend was alright, merely stunned.
Dean blinked. "Wait… so killing Dick was a direct pass to this place?"
"I guess."
Dean started to say something—something about weapons—but rustling in the bushes nearby diverted Castiel's attention.
Castiel froze. I should have known. An angel in a place like this… of course it will attract the attention of every monster here.
His eyes flit between the surrounding trees and Dean, who was still unstable, recovering from their unexpected trip to the Hell-adjacent land.
If they come for me, Dean will only be a casualty. I have to go.
With a silent apology, Castiel launched himself into the air.
Dean turned to say something to Castiel, but his friend was already gone. The angel heard his friend call his name, panicked.
But he couldn't go back now. If he did, Dean was dead. If he stayed away, at least Dean would have a chance.
He fled as a pack of monsters closer in on his best friend, praying to anyone that would listen that his friend would be spared.